US centrism. I tried to unsub from the worst offending communities, but I still am unable to scroll down a page without seeing something obviously only relevant to the US or tainted by yankee culture. posts and comments assume everyone is USian and anyone who isn't is treated like a foreigner.
It made my mood worse, affecting my daily life. So I cut down, and now I barely go there at all.
Lots of Chinese stuff that lack subs. Often it's only available on bilibili, too.