OpenAI CEO Sam Altman said at Sequoia Capital’s AI Ascent event that ChatGPT usage now breaks sharply along generational lines. Older users tend to treat it as a Google substitute. People in their 20s and 30s use it more like a life adviser. Gen Z, he said, is using it like an “operating system.” Altman added that some college-aged young adults do not make major life decisions without first asking ChatGPT what they should do.
Three distinct patterns of use
Altman described three layers of adoption. The first is basic search-style behavior: users ask a question and get an answer, much like a traditional search engine. The second layer goes beyond lookup. Users in the 20-to-30 age range turn to ChatGPT for career questions, relationship issues, and financial decisions. Gen Z sits in a different category. For that group, ChatGPT is not just a tool for isolated tasks. It has become part of the structure around how work gets done.
Lecture notes, cloud files, calendars, and dev tools
According to Fortune, Gen Z users are integrating ChatGPT far more deeply than casual users. They connect it to lecture notes, PDF files, cloud storage, calendars, and even development tools. They also build reusable prompt templates for writing, research, scheduling, and software development. That is why Altman chose the term “operating system.” The point is not literal replacement of macOS or Windows, but that AI is acting as a persistent layer across multiple tasks rather than as a single-purpose app.
18-to-24-year-olds are the fastest-growing cohort
OpenAI’s official report from February 2025 said that more than one-third of Americans aged 18 to 24 are using ChatGPT, making them the fastest-growing user group in the country. Another data point cited in the source says 70% of Gen Z uses AI tools weekly, compared with 20% of baby boomers. The figures line up with Altman’s observation: younger users are more likely to fold AI into recurring workflows instead of turning to it only for occasional answers.
AI moves closer to the decision process
The divide Altman described goes beyond familiarity with a new product. For many older users, AI remains a helper. For younger users, especially college-age Gen Z, it is starting to sit inside the decision process itself. The source frames this as a widening gap in cognitive habits, not just software usage. There is no settled conclusion yet on what that shift will mean over time, but the level of ChatGPT adoption among younger users already shows that this is no niche behavior.