Bottom line: These people, weather they are arrogant, impolite or unsympathetic to users does not refute the fact that they are giving their time to the project.
GNOME has been under fire since the famous GNOME 3 release and I would understand the remaining developers to be a little touchy on the matter. At some point, you either stop - or you decide: Fuck this - I will just ignore user-input, because it sucks.
There is nothing more demotivating for developers (especially those working for free) than a loud group of people displeased with your work.
Do I agree with the way they communicate back to the community? Hell no! But they only deserve half of the shit storm they are getting.