If you can reduce a problem to a point where it can be solved by simple code you can get the rest of the solution very quickly.
Reducing a problem to a point where it can be solved with simple code takes a lot of skill and experience and is generally still quite a time-consuming process.
The open question is why people needed fancy AI tools like Claude to write CRUDs in the first place. These kind of tasks ought to be have been automated a long time ago.
People have been trying for literally decades. The problem is that there is just enough uniqueness to every CRUD app that you can't really have "the CRUD app".
I guess it's the sweet spot for AI at the moment because they're 95% all the same but with some fairly simple unique aspects.