I see two main problems with this approach:
1. productivity and quality is hard to measure
2. the codebase they are ruining is the same one I am working on.
> 2. the codebase they are ruining is the same one I am working on.
We're supposed to have a process for dealing with this already, because developers can ruin a codebase without ai.
See point 1.
I don't understand. Presumably you have code reviews to stop coders committing rubbish to the repo?