The YouTuber Carl "Sargon of Akkad" Benjamin, and the feminist social justice activist Thomas Smith had a debate at Mythcon 2017. At one point this exchange between them happened:
Thomas: "I'm in favor of making things more equal."
Carl: "Ok, but I'm not. I'm for making things more free, and freedom will never cause inequality."
Thomas: "Freedom entails discrimination. Freedom allows white men to control everything."
Carl: "Oh my God, you are a white supremacist. You are actually a white supremacist with a guilty conscience."
Thomas looked completely baffled at this response. Clearly he just couldn't understand what Carl was saying, or why. I bet that it felt to him like completely nonsensical and out of left field.
I think Carl Benjamin is completely right here, in a sense. Thomas might not be consciously and deliberately a white supremacist, but he's unwittingly being one.
White supremacist (actual white supremacists, not the "everybody who disagrees with us" "white supremacists" of the SJWs), at large believe in the innate superiority of white people. They believe that all other things being equal, a society consisting of white people will always become more advanced than a society consisting of other kinds of people. (Some white supremacists might believe this is because of genes, ie. that it's an inherited trait. Others, perhaps in a sense a bit less bigoted ones, might believe that it's because of the long history of culture and scientific and technological progress that has happened mainly among societies that consist predominantly of white people.)
One white supremacist expressed this with a thought experiment: He suggested that if all the white people living in Europe were to move to Africa, and all the black people living in Africa were to move in Europe, in a few decades, or perhaps a century, their status as predominantly "first world countries" and "third world countries" would switch. His argument was that it's not the natural resources and geographical location that determines the economic and social status of a country, and the technological, scientific and social progress of that country, but the kind of people that live there. In his view, white people would make the countries just work and prosper through knowledge, experience and hard work, regardless of where they are.
When Thomas says "freedom allows white men to control everything", he is implying exactly that: He is implying that everything else being equal, if the freedoms of white men are not restricted, they will naturally eventually control everything. They will raise to the top, and be above everything else, dominating all the top positions. He is implying that the only way to stop white men from doing this is to restrict their freedoms. He is quite clearly implying that these restrictions ought to be imposed only onto white men, not anybody else. Only white men need to be restricted in this manner.
In other words, he is unwittingly claiming that white men are inherently more capable and more powerful than everybody else, and if their freedoms are not restricted, they will control and dominate everything, even if everybody is given the same opportunities in life. This is precisely the white supremacy ideology.
He is, by far, not the only social justice warrior who thinks like this, and doesn't understand why they are unwittingly white supremacists.