It has some features Id love to see on ActivityPub like account migration between servers, and people are already working on bridges between the protocols so it will basically be able to federate, at least with mastodon. I was also skeptical but if they keep it open source and let it play nice with AP protocall I wont be mad at it. Sure I'd prefer them pushing AP further than doing their own thing but for whatever reason I'm willing to give more benefit of the doubt to them than a service like threads.