I don't know enough about it to give feedback. However Martin Kleppmann's[1] involvement is a huge selling point to me. It's also, seemingly, good enough that they're building very useful things on top of it like PDS, migrating users, etc.

ActivityPub (AP) felt a bit like "good enough to get something done", which is amazing on one hand - people can do a lot with it. But it also means some harder problems are totally ignored[2], so the landscape between instances felt rocky to me. I also heavily disliked how federation worked in AP, ie how the protocol felt like it favored centralized instances because small instances were less likely to be pinged, were lower priority, in general was very spammy, etc. Not that the AP proto did anything to cause that.. it just didn't do anything to address it in my view, it was just data.

Does AT fix my concerns over AP? No idea. But i appreciate a proto that had a bit more time in the oven and being used to (maybe) solve the harder problems that i experienced with AP.

[1]: https://arxiv.org/abs/2402.03239 [2]: These are only my opinions from a very brief stint in trying to write an AP client to federate with Mastodon, Lemmy and Kbin. I did not dive deep into AP, so please don't judge it from my experience.