i think that while it had it's own host of problems it was really the ideal social media.
multiple media formats were supported. it was easily searchable. the ui was perfect; minimalist, iconic, but also customizable. while there was some kind of recommendation algorithm it really was just largely user-sourced: you followed specific blogs, specific tags, and that ultimately led to a super rich online experience where for certain the stuff you wanted to see was on your timeline and if you saw something you didn't recognize but liked (or something you recognized but didn't like) you could actually change your feed to include (or exclude) that new content, which more often than not came from people / tags you were already following
subculture on tumblr flourished in a way that instagram and twitter have never replicated; the fact that you could follow a$ap yams, frank ocean, et al and be tapped into this new moment in art and media or be in the pits of fandom tumblr or just be somewhere in the middle and constantly see cool photos, essays, etc. (where again, all of this is indexed on specific tags so people can post common stuff on the same thread) is just so much what the ideal digital platform is (for me, at least) - and unlike ig and twitter, you could be multi-faceted on tumblr; the algorithm (or your followers) didn't punish you for liking and posting about multiple things
instagram has carved its niche out by asking users "how monetizable can you make yourself?" twitter has carved its niche out by asking users "how disaffected and aloof can you make yourself?" tumblr was the only place where you weren't actively punished just for being earnest. it's still around but it absolutely isn't the same and the second someone can make a website with the exact same feature set without getting sued i'm so fucking there. pi.fyi is the first site that feels "tumblr-esque" in a while (honorable mention to are.na which i just haven't had the patience to figure out yet)
