That's your opinion. Others would say the greater asshole is one who refuses to confront morons with their own moronic behaviour. That person is denying the moron opportunity to self-reflect and improve themselves.

And before you interject, I would also assert that numbing the confrontation with "civility" also nullifies the effect.

Depends. If people are morons, you can call them like that and not be an asshole, just honest. Don't know about this case, though ...

Even being right, you can still be a jerk.

Though being wrong and a jerk is definitely worse in a sense, personally I think that attitudes that qualify you as being a jerk only marginally help you in being honest.

The basic idea is that even if someone is a moron, calling them a moron isn't really.... doing much. Very little information, and a lot of rudeness. Telling them that their patch isn't mergable has more info and less raw rudeness IMO