In my days, this was called a simple CRUD app, not a CMS. While technically being a CMS, many things would fall under this category that clearly are not.
Now AI will have a breeze creating a simple CRUD proccess, especially if you invest some time. However as soon as it gets even a bit more complex, in my experience everything starts to fall apart.
However I think it's really nice that people, coming from a different background have a way easier time, getting into coding than I did when we had to StackOverflow every single thing for hours. It can be a real learning-boost if you apply AI correctly. And from the vibe, that's what I am seeing this person getting out of it.