To decolonize the mind is a tough thing to do. It is ironic that the people who don't like it, merely don't like it because it doesn't show whiteness (not white people, but whiteness) in a bad light. That should tell you all you need to know. As for the documentary itsel, parts are hard to watch. He makes you sit with your feelings and endure the cognitive dissonance within you. Even paused a few times to "research" only to find out, what was just said/presented was factual. The narrative around a lot of what we know and was taught is torn down and that is extremely hard for some. Like finding out the Easter bunny, tooth fairy, and Santa clause aren't real. The documentary does a great job of humanizing the people while showing how whiteness (not white people) developed a sense of being in this country. It is worth a watch and when you get over the emotions of it, you should watch it again. I can not lie- I did wonder how this snuck by to be on such a large platform like HBOMax. But it was well worth discovering.
Disregard the sensitive cancel culture firebrand of those who just want to call anything that doesn't say "white is right, regardless" political drivel or propaganda - as if the status quo isn't propaganda in the worst form.