III wasn't half-bad. If the rest of the prequels had been like that, they'd still be sub-par, but not nearly as hated. I was bad, but oh my god, for the brave few fans who went to the theatre, they soon found out that things could indeed get a whole lot worse in II. The fact that people went in at all is brand loyalty at its finest.
Protip for dealing with Sherlock in the future: just assume he's going to be an asshole, and he gets way easier to tolerate.