I hadn't heard of the term before but I can see how it would be a fun thing to spread on Tumblr in particular where it's so easy to upload visuals.

But I do know what you mean about missing the energy of discussions and localized events. I remember reading someone talking a while back about how much less crack fic there is these days. One reason is the lack of communities in places like Tumblr and the other is that places where it can still happen like that, Discord, is all closed off so activities don't spread more widely.