> For a person (senior or otherwise) to examine code or configuration with the granularity required to verify that it even approximates the result of their own level of experience, even only in terms of security/stability/correctness, requires an amount of time approaching the time spent if they had just done it themselves.

Hell, often it feels slower/worse. Foreign code is easily confusing at first, which slows you down - and bad code quickly gets bewildering and sends you down paths of clarifications that waste time.

So many times I get AI generated PRs from juniors where I don't feel comfortable with the code, I wouldn't do it like this myself, but I can't strictly find faults that I can reject the PR with. Usually it's just a massive amount of code being generated which is extremely difficult to review, much harder than it was for the submitter to generate and send it for review.

Then often it blows up in production. Makes me almost want to blanket reject PRs for being too difficult to understand. Hand written code almost has an aversion to complexity, you'd search around for existing examples, libraries, reusable components, or just a simpler idea before building something crazy complex. While with AI you can spit out your first idea quickly no matter how complex or flawed the original concept was.