1: Yes.
It is probably preferable, to not use the feature/function for your use case. First in chat 20 people are gonna !clipit at the same time, which I hope only results in one clip to save 20 clips being made. Second the clip is owned by you and not the person who won the !clipit race.
Which means you have a clip, that is incorrectly titled and incorrectly cut to length.
I think it’s better to not use this feature like this and let people alt+x or just use the clip button. But thats my opinion.
2:
As documented
it’s a GLOBAL rate limit only, not a helix rate limit.