The key is that there's a pre-existing ecosystem and you're trying to get into it. It's got its rules, mechanics and politics. You come in with a slightly wrong angle (which is most likely the case) and you'll get an immediate "f*** off" type of reaction. Expecting those inside to be "reasonable" is likely unreasonable as they didn't get in by being nice guys, they got in by sticking around long enough or something else other than an "I'll be nice with everyone" attitude.
That said, I personnally find the [range of: "occasional" to "extensive"] use of off-hand labels by prominent developers simply counter-productive, especially for the casual/non-involved observer. Reading that so-and-so said that foo-bar's patch was "crap" or "bloated" gives me no information whatsoever. Maybe I'm just dense, but I, for one, would have no indication as to how to proceed next.
Then again, I can't recall the exact name of the guy, but apparently one of the people who worked with Jobs got into an argument with him regarding an idea Jobs didn't like. Apparently it got pretty heated and the guy asked Jobs something like: "Then what exactly do you want?" To which Jobs replied something like: "I'll tell you when I see it." That, at least, is pretty clear.