Speaking for myself - they may not have cared to.

I can absolutely prompt AI to following established patterns and produce nice, clean output in a legacy codebase. I also have a completely separate set of skill files that I’ve been building organically by allowing the agent to do make most decisions about conventions. The latter produces code that would be a nightmare to modify by hand, but I’m still able to iterate on it many times faster than I could in the codebase where code quality is a requirement.

“Code quality” is mostly “human readability”, and I’m simply not sure that’s a valuable attribute anymore.