And to be fair, even though it exists, there's a huge majority that is done manually, even though it needs zero or very little manual "creativity" between specification and implementation
Let's take parent poster's issues:
> Writing HTTP endpoints, parsing json. Mapping data types.
The generative model (for now) won't figure out for you: authentication, authorization, input form schema, JSON schema, required & optional fields, field constraints, entity modeling, indexing, query optimization, just to name a few basic issues we are looking at when "just developing CRUD apps".
If any of those go bad, it would result in 400s, 500s, performance or security issues.