They've been in a roll nerfing stuff like this ever since MS bought them. See "load more comments" ajax links when there are more than 10 comments in a PR revie

They've been in a roll nerfing stuff like this ever since MS bought them. See "load more comments" ajax links when there are more than 10 comments in a PR review, or "load diff" when a file has changed more than a few lines. All of these degrade the ability to actually look at changes and review them, which is kind of the whole point of pull requests. But alas, the enterprise must enterprise.