Why is racism towards white people socially acceptable?

Just to clarify, I'm wasian and in NO way do I condone racism from any race to another, but in the big city I live in and especially online, it's completely fine for people to say stuff such as, "All white people are evil!", "White people are crackers!", "Crusty white people!", etc. Those are just a few examples. Although, if you said something degrading another race, you have an army of people attacking you. With that being said, I do get that white people have been oppressive to POC for centuries, but it seems that now they seem to be the least racially-concerned as generations continue. What's up with this?

Why is racism towards white people socially acceptable?
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