A lot of youthg are "left", it's not a big secret. Kpop are a kind of a youth movment so it's not strange a lot of kpop followers are "left". The "left" is also more likely to accept different cultures and people from other contries. So do you think it's strange that members on a forum with a low average age that talk about music and artist from a foreign contry is "left"?
It's just that demographic of the forum that make it that way.
Yeah I think that's what brought them here for sure.