Hard to believe Tumblr lasted this long even. They killed like 3/4 of their content (and audience) when they decided to not have any porn like 4 years ago. Everybody left. An early example of enshitification.
No website (that I've ever found) has quite managed to replicate how tumblr works in terms of discovery, customization, community, and organization, so some people prefer to put in the work for the sake of using a format they prefer.
I really like Tumblr (mainly because RSS support), but I find their search VERY limited. Maybe I'm being stupid, but I haven't been able to search for 2 tags at the same time (e.g.: "#artists on tumblr" and some genre "#pixelart").
In general I find very difficult to filter repost and look for original content only.