Not entirely wrong, but there's a very big hole: "the scaffolding produced by the team" also includes the scaffolding produced by past AIs.

An AI that knows how to keep the documentation accurate and up to date, and does it by default, would, all other things equal, rot your codebase less. An AI that changes the code without checking whether it obsoleted a bunch of examples in the docs would rot your codebase more.

While I think that you can reduce "AI-induced code rot" with good prompting and steering, you could also make headway against it at model level, by making the AI "well-behaved" by default.