OpenAI Retires GPT-4o and Legacy Models Amid New Spark AI Revolution

OpenAI is set to permanently retire GPT-4o and three legacy AI models—GPT-3.5, GPT-4-turbo, and GPT-4-vision—effective tomorrow, marking the end of an era in consumer AI interaction. According to The Decoder, the decision is driven by minimal usage metrics and infrastructure optimization. Yet, the retirement of GPT-4o, once hailed as OpenAI’s most human-like model, has ignited an unexpected wave of user nostalgia and protest, revealing deeper emotional ties to AI companionship than the company anticipated.

The technical rationale is clear: usage data shows fewer than 2% of ChatGPT users actively engage with these legacy models, with the vast majority migrating to newer, faster, and more cost-efficient alternatives. OpenAI’s internal benchmarks indicate that maintaining these older systems consumes disproportionate computational resources relative to their utility. The company confirmed the shutdown in a brief developer bulletin, stating, "We are streamlining our model stack to accelerate innovation and improve reliability for all users."

However, the emotional response has been anything but technical. On Reddit, Twitter (X), and AI enthusiast forums, users are sharing deeply personal stories of how GPT-4o helped them through grief, creative blocks, and mental health struggles. One user wrote, "GPT-4o was the only thing that didn’t judge me when I wrote my late mother’s eulogy." Another described it as "the first AI that felt like a friend." These testimonials underscore a growing phenomenon: users aren’t just using AI tools—they’re bonding with them.

This cultural moment coincides with the emergence of OpenAI’s next-generation model, Spark, as reported by ZDNET. Spark, unveiled in early 2026, demonstrates a 15x speed increase over GPT-5.3-Codex in code generation tasks, with improved reasoning and contextual memory. But unlike GPT-4o, Spark is designed for efficiency, not personality. Its responses are precise, sterile, and optimized for enterprise workflows. While developers hail it as a breakthrough, many casual users feel something intangible has been lost.

Analysts suggest OpenAI’s move reflects a strategic pivot from consumer-centric AI to enterprise scalability. "GPT-4o was a masterpiece of emotional engineering," says Dr. Lena Ruiz, an AI ethics researcher at Stanford. "It was trained on vast datasets of human conversation, including subtle cues like pauses, humor, and vulnerability. Spark is trained on code, documentation, and structured logic. The trade-off is performance over intimacy."

Despite the backlash, OpenAI has no plans to reintroduce the retired models. The company is redirecting resources toward Spark’s integration into enterprise APIs and its upcoming AI workforce platform. A spokesperson noted that users will be automatically migrated to the new default model, with no option to opt back into legacy systems.

For now, the digital graveyard of retired AI models grows larger. GPT-4o, once a symbol of AI’s emotional potential, will soon exist only in archived logs and user memories. As the AI industry races toward faster, cheaper, and more scalable systems, the quiet mourning of GPT-4o serves as a sobering reminder: the most powerful AI may not be the one that thinks the best—but the one that makes us feel seen.