That's not gonna fly for any established business, or any business that will become established. For one thing, you can't delete customer data and start anew. You also don't want to break existing links or you suffer SEO. Maybe you intentionally segregate rewrites to only stateless parts of your application, but at that point you need an expert human to architect. Or maybe you ask the AI for migration scripts, which is even harder for AI to solve, and hard to expect the layman to follow instruction properly.

Code/schema/system generators already exist for various parts of tech, and the one hardest problem to solve have always been modification.