Agreed, but to be fair, /pol/ was created with the officially stated goal of acting as a containment board. And tbh, that’s exactly what it still is to this day.
Survivorship bias, evolutionary somethings, and curation help the shit escape 4chan's confines. I can probably word that more eloquently when my brain isn't fried.
If you happen to get footage of a "happening" and post it on 4chan, people will notice (and call you various slurs).
If you post it anywhere else it's liable to be deleted, or worse, ignored.
It can be made again. But whoever does it has to learn from past mistakes.
This model attracts all manner of idiocy and hatred, and it's much too easy for one provocateur to hijack the system. The result is that the site requires several containment zones like /b/ and /pol/.
However, the upshot of 4chan (or any imageboard, really) is the total lack of narcissistic incentive. If you stick to blue boards, consciously avoid the containment zones, and you ignore the provocateurs (big IFs, I know), 4chan hosts some remarkably eclectic discussion of the arts, science, and entertainment. It's really good at elevating things that are thought-provoking or avant garde, if only within the bounds of a polarizing and inaccessible platform.
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.