I have a few decades programming experience, as a professional software engineer, an open source developer, and a DevOps engineer. There is no way in hell I would do a code review where 15k lines were added and a similar amount of lines removed without having a long discussion with the person who made those changes. I’d want to ask a lot of detailed questions about the changes, questions that an LLM isn’t likely to answer, and most definitely not questions I’d be inclined to try to type into an LLM to try to get an answer.

Over the years I’ve dealt with all manner of bugs, from overflows & underflows, to bad assumptions about logic flow, and much much more. The whole purpose of pointed questioning of the author is to be comfortable with decisions made in the code and to minimize the chances of all sorts of potential bugs.