I think it's disingenuous to say that these sites do not attract certain types of people over other sites. It can likely be attributed to the personalities of the people who take off and become popular as well as those of the moderation staff. Can you seriously say that tumblr and 4chan (or the *chan of your choice) share the same atmosphere and posting habits? They're both large scale websites where anyone can come and post whatever right?
pretty true though, the site's reputation will obviously attract people that favor that environment. it's just not really
anywhere and everywhere like people seem to think. it's pretty contained because the site doesn't ever promote content unless you tell it to (aside from ads). you can stay in your little box of tags as much as you want. if you go looking, it's pretty easy to find because all you have to do is search the relevant tag, but unless you follow that tag or follow someone that's like that, you will literally never see it.
Considering you yourself are an SJW it's not at all surprising that you don't see "what people are talking about".
it's pretty easy to spot this kind of stuff. i barely see
anything political at all aside from some minor political blogs i follow and stuff my buds reblog. my dash is filled with art and stuffposts and i plan on keeping it that way
the problem with tumblr is that the whole personalized content stream stuff, while generally benevolent, allows those kind of reality-detached communities to form via conditioning some people to believe that the rest of the internet should be like their personal content stream while imbuning them with the self righteousness only a personal stream of content agreeing with someone can form or some bullstuff i dont have any sources. also the vast majority of tumblr is fine
yeah, this is a pretty big issue with the internet in general, it's really easy to only see what you want to see and that can warp a lot of people's world views. bonus points because literally anyone can post anything on the internet for people to see.