In terms of "engagement” (lol), bluesky and tumblr are both ahead of the fediverse right now. But what interests me isn't the numbers so much as the patterns.
Tumblr's tag culture, and posting culture in general, means people go back to older posts on accounts like this a lot more often. Both the fediverse and bluesky are more about looking at the latest posts from accounts, so old posts don't recirculate often except when someone first follows the account. Less interesting that way.