I'm not the poster you replied to, but I'm going to assume that you just don't know any better. >has been flooded by torrents of cheap white-supremacist propaganda targeted at young boys to destabilize and undermine the western society.
"White supremacism" as in the textbook definition (not white tribalism, but this whole supremacist idea that makes whites look like comic book villains) was itself a sign of a controlled group, specifically in America: the KKK, Rockwell's NSWPP, etc., thus the pushing of "white supremacy" is really a tool of anti-white agitators to blackwash pro-whites; I'll call this "faux-nationalism". 4chan was never "pro-white" but some people on /b/ ironically tried to imitate faux-nationalists for shock-value, this was manifested more clearly in /n/ and eventually, there were some actual white nationalists in later /new/ and /pol/. However, the demographics of /pol/ nowadays hardly consists of these kinds of people, let alone genuine pro-whites; in-fact, just like the KKK, they're essentially projects of faux-nationalist agitation. More often than not, a lot of these "white nationalists" hate all whites (typically jewish agitators themselves). They'll say that the British aren't white, Irish aren't white, Scandinavians aren't white, Dutch aren't white, Finns, Germans, Italians, Poles, Balts, etc., while the next thing they do is push for whites mixing with Asians because they're "traditional", blacks dominating white women or even white men, all sorts of pilpul used to justify degenerate fetishism common among jews (homosexuals, pedophiles, transvestites), etc.
All of this jewish agitation can be easily explained by the idea that jews now control 4chan as a propaganda tool (specifically /pol/. /his/, and /lit/, not so much the other boards). Ever since 2011, 4chan has been literally funded by jewish bankers, and thus relied on other wealthy jews (not just m00t/Poole himself, and he was already a degenerate and most-likely has jewish ancestry) kept up as a website and more importantly, government agencies have been plaguing the site even before that, thus it's not unlikely that it can be used as a tool of psychological warfare. Just because the content there may sometimes be "anti-jewish", it doesn't mean that it's not "run" by jews. More-specifically, not just their funders, but I'm talking about jewish moderators, actual jewish agitators that post on the board, and chatbots that have "learned" how to use pilpul. It's pretty obvious to see how they communicate based on what they push, and it's also easy to see their influence on young whites. As I said earlier, pro-miscegenation of any kind, cancerous overused memes like Wojak (specifically as "Soyjak") and Gigachad, attacking or strawmanning white culture, actual pro-Trump/Putin posts and most importantly, pro-negroid posts and negroid slang. Words like "based", "woke", etc. are all over not just 4chan but also the entire internet, indicating that the negrification of whites worldwide has skyrocketed since the 1990s.
Even slower boards like /his/, /sci/ and to a lesser extent, /lit/ are also awful nowadays. I'm not going to even talk about any of the other boards as they're basically just degenerate central. Thus a jewish "control" of 4chan is undeniable.