I don't work for GL but I'd be interested to hear what you think makes the GL pull request functionality inferior (my guess is you're going to say the number of "actions" available that target the GH API but it's just a guess)
Sometimes diffs are bad (I would bet github uses diff -ow, or something similar) and in general PRs are a drag.
Typing out 85 review comments and having them swallowed by a 500 response because the frontend thought that of course XHRs are always 200 OK, why wouldn't they be? is indescribably infuriating
If I had more energy, I'd try that on some big MR to just to find out whether their stupid extension also just assumes all XHRs are 200 OK. That'd be some icing on the cake
1. POST /review/temp
1. POST /review/temp
# all done, submit the batch
1. POST /review/submit <- 500 Oops we sorrwweee
# now every comment is gone
And yes, "extremely pissed" isn't strong enough but ... put it on the list of the other 48,000 issues, I guess