I reckon most newer users (myself included) came here because it's probably the only truely anti-censorship internet community left, as such that's how they percieve it and they don't respect it's original purpose as an entertainment/gossip forum. Some of us get the culture and keep the aggressive sperging and irrelevant posting to a minimum, others get carried away and seem to blow off years of steam from having to hold their tongues everywhere else. It doesn't help that some are coming from places like facebook where pointless filler posts are the norm and even rewarded with empty validation (shit like the first comment under an absurd photo being like "WOW.....What even

" - 2.4k likes).
As long as other internet communities are continuing their totalitarian ways of upholding huge biases and booting wrongthinkers, the newfags aren't going to stop any time soon. They're going to treat it like their own personal club where they can farm updoots and unrelentlessly rage at percieved outsiders and political opponents because thats exactly the kind of environment they came from.
Long probation periods, continuously driving home the points of this OP and some form of retarded newfag hall of shame are the only solutions I can think of.