I was wondering too, but the only results i found were their announce that they could me interested in joining fediverse, sad

No, latest update is from early this spring, with no updates since.

If you follow their lab, wip and their weekly updates (changes), you can see things being rolled out at a snails pace that are required for a fully fledged fediverse platform.

Polling, self moderation, notifications, etc. but it’s taking a looooong time…and there’s really no incentive for their devs to invest time in it, right? Because I won’t be seeing ads if I view tumblr content from my Kbin client for example.

I’m still having a hard time understanding why meta cares either. More audience for branded / sponsored posts?

https://changes.tumblr.com/
https://www.tumblr.com/labs
https://wip.tumblr.com/