I think this is a narrow position. On the boards on chans that I frequent, this isn't at all true. Yes, there are occasionally "trolls" who pretend they have positions they do not. The sarcasm may be subtle or not, depending on intention. But far more predominantly there are people who espouse their views and back them up cogently. There are also devil's advocates.
But I wouldn't say that chan culture is about this, or that there is an inextricable link between them. It's simply a common occurance by nature of being anonymous. More often than not, "bait" is called out as such, but even if you're being serious, you can ignore that.
A mixed bag, but certainly not representative. I know of many on the politics board who do sincerely hold nationalist or white supremacist views, and I have argued against them. I also know many on the left-politics board who will talk you through Marx's critique of capitalism.
There is some nuance in my opinion.