The quotation marks around "as racist as they come" indicate disagreement in this case, and not agreement (so, no, I'm not agreeing in one sentence and then calling it hyperbole in the next). I agree that there are *some* very racist leftists, just as I think there are *some* very racist centrists (that's a given, I think). But what you wrote is hyperbolic, and it's not useful precisely because the same phrase could be applied to self-proclaimed centrists or any other group. I've been critical of Sanders and his supporters (see the first link in my previous reply), but any suggestion that he's "as racist as they come" (see KKK and neo-Nazis) is hyperbolic. And your average Bernie Sanders supporter (outliers aside) has got nothing on the likes of Stephen Miller or Steve Bannon (much less your average KKK member).
But let's put aside the question of whether or not what you wrote is hyperbole, as that's beside the point. Of course I agree there are self-proclaimed leftists who are racist. No doubt about it. There are racists in every group, as you suggest, though there are without question far more among self-proclaimed conservatives/Libertarians/Republicans. This is a white supremacist, patriarchal society in which we live, after all. Hell, there are racists who voted for Obama.
As for The Platform of TM4BL, I don't think it's extremist. I think it's perfectly reasonable, incredibly thorough and something that should be read by everyone (that's why I've posted a link to it in a variety of posts/contexts). But the dominant narrative in this society would say it is extremist, while the likes of Collins and McCain are "moderate," which is absurd. People need to recognize that allowing that narrative to take hold has ceded turf to the GOP.
Really, the main point I've been making is that people are using these terms haphazardly without defining them. As I posted in my thread asking people to define "centrist":
I'm wondering what everyone considers to be a centrist position on specific issues. Everything from health care to taxes to higher education to climate change and environmental protection in general to gun control to equal pay for women to wages in general to immigration to capital punishment to drug laws to defense spending to LGBTQ rights to all that which is in the platform of The Movement for Black Lives.
Nobody seems willing to do that, which suggests most who use terms like "centrist" or "extreme left" haven't thought critically or specifically about what those terms might mean. If we hope to combat the narrative mentioned above, which has unfortunately established roots, we need to stop and think critically instead of going along with said narrative. But, instead, mostly you just see vague comments like "centrists are those between the extremes." What the hell does that actually mean?