I experienced problems with this too, though I would narrow it down to elitistic programmers & low level experts, which are naturally found in #Linux centric comminities. Especially, those who think, C is still the best thing ever & if you aren't for it, you are apparently too stupid to understand computers.
As for #Linux & #FOSS in general, I have experienced plenty of n00b communities, which are the opposite of elitistic. They help out newbies, even with the "easiest" questions, without making them feel bad.
But if you join a #community about a complicated product, then you most likely will meet someone who is registered on the forum for 20 years & everyone else is supposedly stupid, because nobody has that much knowledge about the product in question.
The first spontaneous example that arrived in my mind right now, when thinking about this is the #OpenVPN forum & its "TinCanMan" or whatever that dude is called.
He is an utterly elitistic anti-helper, who basically always shames you for not reading the entire 500 page #OpenVPN manual & understanding everything right away, without any questions, despite the fact that typical #Linux manuals are always shit, because they only define stuff, rather than just giving an example.
An example of five lines explains thousand times more reality than a hundred lines long definition, in my experience with #Linux like manuals.
So, based on that example, I think one of the stupidest anti-help things in #FOSS communities is that attitude, that before you ask ANY question, you first must read 500 pages of a manual or you don't even qualify for a question. That's just mad, because it's denying reality, like the fact that usually people use several products at once & they cannot just read 1500 pages of 3 manuals before asking one question.
The other toxic thing that arrived in my mind right now is one dude on the #ArchLinux forum. There is one guy, forgot his name, but everyone will easily find him, because he's almost in every thread, who always shames everyone for not understanding everything about #ArchLinux right away.
Needless to say, I think the #RTFM tag is utterly bullshit in many scenarios, where manuals are way too long & too complicated & don't even offer examples & sometimes they are even outdated, as well.
#FLOSS #Eliticism #Clang #TechSupport #Newbie