AI doesn't preclude this. In fact, it can help accelerate parts of it.
He's describing the typical big project lifecycle:
- Examine the landscape
- User research (how they use existing software, what their frustrations are, etc)
- Brainstorming
- Early ideas and prototypes
- Refinement, user feedback
- Solidify the vision and high level process design
- Choose technologies
- Design & architecture
- Plan out phases
- Build phases, then test them with users
LLMs are great at research, and great at prototypes. Once you have your design, they're good at coding as well. They're also good at distilling user feedback.