4chan is unique because of its combination of scale, relative lack of moderation, and relatively high anonymity. By nature, it's a place where political radicals would be able to shitpost freely en masse. 4chan was absolutely a vehicle for platforming radical politics, but the word "shitpost" is key - the average discourse on 4chan isn't at a level where ideological formulation can happen at a meaningful scale.
Memes are the only exception. 4chan memes have, on multiple occasions, turned into widely-known (and sometimes widely-misunderstood) political imagery. That imagery routinely has no clear symbolism whatsoever, and is assigned all kinds of wacky meanings depending on you ask... which is what you'd expect from 4chan, I guess.
