I'm just going to note at this point I personally have very little inclination to try and convince people that white supremacy is real. I will simply note that someone from a British family raised in a country that Britain historically colonised (and still owns a bit of it, in fact), there is a lot of needless defensiveness over being honest about one's country's own history.
I was raised in the school system of that ex-colony, and a good chunk of that history is the impact of the British empire on that country. There wasn't any hatred, or attacking, but it was frank, and it was truthful and it didn't shy away from acknowledging that this happened, and it still impacts life between those countries today. As someone who's been through that system, I have basically no animus or hostility to talking about these topics. In Britain today, it is the people who haven't been educated in their country's own history that are the most hostile to it.
And this is how I tend to look at this debate. The people who are most angry and defensive and upset at having to talk about these topics at all are almost always the ones who know least about their country's own history, or are least willing to face it, or haven't had to be on the receiving end of this kind of discrimination. I have little interest in wishing to convince such closed minds, hence my general disinterest in this for some sort of conversation.