I have seen two main complaints:
* This is opt-out not opt-in, and I don't like that.
* BlueSky is bad because it is run by a company (sometimes with a suggestion that Jack Dorsey owns and runs the place), and I think the fediverse should be free from corporate influence, and so I object to the idea of a bridge.
Yes, he, Dorsey, did it. I don’t should discount that one bit!
Should we give him or people like him another chance? Fuck no. History is filled with examples of embrace and extinguish. Let’s wish him luck for AT Proto (actually BSKY; he is not interested in AT; AT is the bait, the lure, because he knows well people will just flock the first and the biggest).
Mastodon is very sensitive to that.
People will still bridge the two in various ways.
People will also bolt on more direct bridging to Mastodon if there's any demand from Bluesky users.
Basically, unless Bluesky totally fails, it will be embraced and extended by the broader broader Fediverse, because why not?