If the BlueSky protocol offers tangible benefits over ActivityPub, the BlueSky protocol could become the basis for ActivityPub 2.0. I don't know much about the details, though.
TL;DR Bluesky is not functionally federated nor decentralized, it is dubious if it ever will be and the layer of post sorting and moderation required to participate in Bluesky's network is extremely computationally intensive and this aspect of Bluesky is NOT open source and is a proprietary black box.
The fediverse and activity pub are the future, even if the current hype train leaving the station (..who is paying for all the free drinks on that train and why?) makes it feel otherwise in the short term.