I also think that AI written code- is just not read. People hate code-reviews, and actively refuse to read code- because that is hard work, reading into other peoples thoughts and ideas.
This is why pushing for new code, rewrites, new frameworks is so popular. https://www.joelonsoftware.com/2000/04/06/things-you-should-...
So a ton of ai-generated code- is just that, never read. Its generated, tested against test-functions - and thats it. I wouldn't wonder, if some of these devs themselves have only marginal ideas whats in there codebases and why.