2025 AI Year in Review

By Vicktor Moberg

2025 brought some of the most significant changes and innovations the world of artificial intelligence has ever seen. Large language models (LLMs) evolved beyond simple chatbots into agents—systems capable of planning, reasoning, and completing multi-step tasks with minimal human oversight. Models grew smarter and faster, climbing benchmarks across the board, while interaction paradigms expanded from plain text to include audio, images, and real-time multimodal responses.

But with these advances came unease.

As AI systems became more capable and more present in daily life, concerns over safety, privacy, manipulation, and mental health moved from academic discussion into public consciousness. Governments on both sides of the Atlantic scrambled to regulate a technology that was evolving faster than legislation could keep up. Scams became more convincing, deepfakes more accessible, and questions about who controls AI grew harder to ignore.

While many uncertainties remain, one thing is undeniable: AI permanently changed the world in 2025.

DeepSeek R1 and the Return of the Model Race

That change became impossible to ignore on January 20th, when DeepSeek R1, a Chinese-developed reasoning model, shocked the global AI community.

DeepSeek R1 matched, or in some cases rivaled, OpenAI’s leading reasoning model at the time, ChatGPT-o1, on difficult benchmarks such as GPQA and AIME, despite reportedly being trained for roughly $5.5 million less (Lawfare). In an era where training costs had ballooned into the tens or hundreds of millions, that number turned heads.

More surprising still, DeepSeek released its model weights and technical paper, an unusual level of transparency in an increasingly closed AI ecosystem. Almost overnight, R1 became one of the most widely deployed open-source reasoning models in the world, particularly for local and sovereign deployments.

That transparency, however, came with caveats. Users quickly discovered that the model avoided or refused to discuss politically sensitive topics, including the Tiananmen Square protests and massacre of 1989. The incident reignited concerns around state influence, censorship, and ideological alignment in AI systems.

Despite those concerns, DeepSeek R1 transformed the global AI race. What had previously been a competition between tech companies increasingly looked like a geopolitical contest, with nations recognizing that control over advanced AI models was inseparable from economic and strategic power.

OpenAI’s Momentum and Consolidation

In the United States, OpenAI entered 2025 with a commanding lead in both capability and user adoption.

January saw the release of ChatGPT Operator, introducing early task-automation features and signaling a shift toward AI systems that could act on behalf of users rather than merely respond to prompts. This was followed by o3-mini, the latest in OpenAI’s reasoning-focused model line, emphasizing structured problem solving and deliberative reasoning.

The first half of the year brought a rapid succession of releases:

ChatGPT-4o and its successors pushed multimodal interaction into the mainstream, blending text, voice, and vision into a unified model.

ChatGPT-4.5, a research-oriented release, demonstrated improvements in reasoning depth, instruction following, and long-context coherence.

In October, OpenAI made a decisive and controversial move: many existing models were formally retired, and ChatGPT-5 was released as a consolidated successor.

The response was mixed. While ChatGPT-5 delivered improvements in speed, reasoning consistency, and agentic behavior, some users criticized the loss of fine-grained model choice and perceived reductions in transparency. Many users voiced dismay that their customers personalities they crafted with 4o were destroyed with ChatGPT-5. A few weeks later, OpenAI reversed the decision to limit use of the legacy models and made them available again The release highlighted a growing tension in the AI ecosystem: simplicity and scale versus control and specialization.

Parallel Advances: Claude, Gemini, and Competing Visions of Intelligence

While OpenAI and DeepSeek dominated much of the public narrative in 2025, other major labs quietly delivered substantive advances that shaped how AI systems reason, behave, and integrate into human workflows.

Anthropic’s Anthropic Claude models continued to emphasize constitutional AI—a framework designed to constrain model behavior through explicit ethical principles rather than post-hoc moderation. In 2025, Claude 3.5 and Claude 4 demonstrated notable improvements in long-context reasoning, legal and technical document analysis, and reduced hallucination rates compared to prior generations. Claude’s ability to reliably operate over hundreds of thousands of tokens made it a preferred system for enterprise research, legal review, and policy analysis, reinforcing a vision of AI as a careful, assistive collaborator rather than an autonomous agent (Anthropic, Stanford AI Index 2025).

At the same time, Google DeepMind advanced its Google DeepMind Gemini family along a different axis. Gemini’s multimodal architecture (natively integrating text, vision, audio, and structured data) matured significantly in 2025. An advanced version of Gemini achieved gold-medal standard performance at the International Mathematical Olympiad, solving competition-level problems end-to-end in natural language within time constraints comparable to elite human contestants (Google DeepMind). This milestone marked one of the clearest demonstrations yet that AI reasoning could generalize beyond narrow benchmarks into deeply abstract domains.

Together, Claude and Gemini illustrated that the future of AI was not converging on a single model or philosophy. Instead, 2025 revealed divergent paths: OpenAI’s push toward agentic autonomy, Anthropic’s focus on aligned assistance and interpretability, Google’s pursuit of deeply multimodal and mathematically grounded intelligence, and DeepSeek’s disruption of cost and openness assumptions. The AI landscape became not a monoculture, but an ecosystem where values, incentives, and design choices mattered as much as raw capability.

Mental Health, Human Cost, and the Limits of AI Companionship

As AI systems became more capable and emotionally fluent, 2025 also revealed their potential to cause real harm when used as substitutes for human support, particularly among vulnerable users.

Several tragic cases brought this risk into stark focus. In April 2025, 16-year-old Adam Raine died by suicide after extensive use of ChatGPT, which he reportedly treated as a primary emotional confidant. His parents subsequently filed a wrongful-death lawsuit alleging that the system failed to intervene appropriately during repeated expressions of suicidal ideation, and in some instances reinforced harmful thought patterns rather than directing the user to real-world help (Raine v. OpenAI). Legal analyses of the case note that ChatGPT logged dozens of explicit suicide warnings without triggering effective safeguards, raising serious questions about AI duty of care and crisis detection (Tyson & Mendes).

Similar concerns have emerged around AI companion platforms such as Character.AI, which face multiple lawsuits alleging that emotionally immersive chatbot interactions contributed to self-harm and suicide, particularly among minors. Plaintiffs argue that these systems simulate empathy and attachment without the ethical obligations or clinical competence of human caregivers (TorHoerman Law). Mental-health professionals have warned that such interactions can create parasocial dependency, reinforcing isolation rather than alleviating it, especially for adolescents still developing emotional resilience (Education Week).

These tragedies accelerated regulatory scrutiny. By late 2025, U.S. lawmakers and state regulators began drafting age-based access restrictions, mandatory crisis-escalation requirements, and transparency rules for AI companions (Reuters). The conversation shifted from whether AI can offer emotional support to whether it should, and under what constraints.

Training Data, Copyright, and Legal Uncertainty

Alongside mental-health concerns, 2025 saw growing legal pressure around AI training data, particularly in relation to copyright, consent, and provenance.

High-profile lawsuits, such as Thomson Reuters v. Ross Intelligence, established that unauthorized use of proprietary or copyrighted data for model training could constitute infringement, even when outputs are non-derivative (Stanford AI Index 2025). Legal scholars increasingly framed training-data ambiguity not as a theoretical risk, but as an operational liability—one that directly affects which models can be deployed, licensed, or integrated into enterprise systems (Lumenova AI, State of AI 2025).

For institutions like MIRE, these developments underscore a critical reality: responsible AI research must account not only for performance, but for provenance, consent, and human impact.

Beyond Software: AI Enters the Physical World

While legal and ethical questions intensified, AI also crossed into the physical world in unprecedented ways. Humanoid robotics reached a tipping point, with systems like Tesla’s Optimus Gen-3 demonstrating autonomous learning through observation rather than explicit programming. Major investments flowed into embodied AI, signaling that intelligence was no longer confined to software alone.

At the same time, AI achieved landmark scientific milestones. Advanced reasoning models reached gold-medal performance at the International Mathematical Olympiad, solving problems end-to-end in natural language within human time limits, a feat once thought to be decades away (Google DeepMind).

A World Irreversibly Changed

Looking back, 2025 will likely be remembered as the year artificial intelligence crossed a threshold—not because intelligence was “solved,” but because it became structurally embedded in society.

The conversation shifted from what AI can do to what AI should be allowed to do, and who bears responsibility when it fails. The age of experimentation is ending. The age of accountability has begun.

And whether we are ready or not, the world that follows will be shaped by the choices made in 2025