In my experience success in a project isn't about the amount of code that can be produced, it's more about the thoughtfulness behind features and fixes. A lot of the work going into reviewing pull requests is understanding it in the context of the project's broader goals.

This gets a lot harder when there is a giant wall of text that the pull requester doesn't understand and can't really discuss outside of asking AI (and probably getting "The reviewer is right to push back - I was too aggressive in my blah blah blah" as an answer).

A lot of (but maybe not all) pull requests are fundamentally a human to human task, even if there is a lot of technical details involved.