it's interesting that some people are on the internet but is very well insulated! AO3 is very well known for me...
Having been an active internet user for longer than most AO3 users have been alive, the first time I heard about it was a few years ago in a student radio show about the fanfic genre and culture. Poorly written smut featuring popular culture characters has just never been my thing. Probably because I’m not that much of a fan of any specific fictional setting or franchise in the first place.
Who is a better judge of what is insulated or not, someone who spent decades living in a single city, or someone who spent a few years traveling everywhere?
(I bring up 4chan because by virtue of being practically unmoderated, it is about as unlike a bubble as you can get. Where else do you get people into origami, hardcore rape porn, international backpacking, nobel prize winning mathematicians, and pranksters running iphone microwaving campaigns rubbing shoulders?)