I hear where you're coming from. I personally don't think the "racist" label is necessarily well-earned in this case, although I do understand that it's a really loaded topic people feel strongly about.
It seems to me that JonTron, within the last several years, probably found himself disagreeing with certain aspects of the social justice movement. That, in and of itself, is not a bad thing. Unfortunately, based on my observations, social justice is pretty much the one topic where there is no room for nuance or empathy. It is powerfully polarizing and most people who who pick a "side" tend to adopt an "all-or-nothing", "with us or against us" attitude. I think that this unfortunate aspect of modern discourse led JonTron to be suckered in by talking points that probably sounded a lot more reasonable when discussed by like-minded individuals who legitimately believed they were under attack and needed to defend themselves.
Unfortunately, JonTron didn't do the leg work of checking to see if these views that conformed to his perceptions held up under scrutiny. He mistakenly thought he had the moral and rational high ground and that that was all he needed to be able to "debate". It turns out that he is absolutely TERRIBLE at debating and the more he tried to defend his stance, the worse he made himself look.
Having said that, I'm not convinced the guy's actually racist or a white supremacist. I think he bit off way more than he could chew by deciding to be vocal about something he needed to shut up and think a little more about, and he's paying a heavy price for it.
I mean, it's certainly possible JonTron is racist. However, I don't think that's an obvious conclusion to draw based on what he said. Furthermore, I find the use of loaded labels to classify people as one of "them" (and therefore allow us to dismiss them entirely) one of the worst side effects of this culture war. I didn't like it when people called Anita Sarkeesian a liar, cheat and con artist, and I don't like that people are calling JonTron a white supremacist. I think it's far more productive to look at why someone holds certain views instead of looking for reasons to conclude someone is the "bad guy".