It just means "white left". It's a Chinese word used by even the Chinese Left. It's used to describe SJW values, mainly those of white saviorism. The Chinese hate the Western SJW culture too. Since they will try to side with China, use it to trigger cognitive dissonance.
Also throw "wumao" at the CCP shills. It's the phrase used to describe the CCP's 50 cent army that types anti-American stuff all day. It's a legitimate thing to use, unlike "Russian bot".
Oh, I was just mentioning that the people who use the words "anime" and "manga" when they really just mean "comics" and "cartoons" in general, use those words in a particularly pretentious way that wants you to assume they have a "higher" taste in cartoons and comics. It's kind of like someone saying they went to "the opera" after seeing Jesus Christ, Superstar.
And it's not that I don't like foreign cartoons, I just don't see the difference in differentiating where something I like is from; I don't see where it should matter, unless the story involves some kind of cultural detail that does make it important. Like taking a moment to figure out why a kid was talking to a ball and calling it "grandfather" in the second scene of the first episode of Dragonball. :P (I know what an ancestor shrine is, but I had to remember the show was from Japan to think of it.)