McCarthy had a complete crap job. I don't mean that because of the ideologies, it would be true if you flipped it.
He was House Speaker with a VERY slim majority and with the Senate and White House controlled by the other party.
Doesn't matter if that situation is held by a D or an R, it is going to be a mess. The party in the (slim) majority in the HoR is naturally going to have people from the wing that want to "burn it all down" but the grown ups need to actually get the business of government done and there are naturally going to HAVE to be compromises because the other party controls the Senate and the White House so the Speaker in that situation is going to have a constant mess on their hands.
Gaetz' criticism is basically that McCarthy passed a budget with more Democrat than Republican votes so his solution was to oust the speaker with more Democrat than Republican votes.