Bridgy.fed is nice for bridging also for using both at the sametime. I think what a lot of people like on BlueSky is the feed algorithm without having to curate yourself like on Mastodon or posts sorted by the time it was posted. That probably makes a huge difference.
It will be interesting to see which one wins out, like how Lemmy won out vs kbin/mbin, since kbin never accepted any outside help and stopped contributing. Not really putting the open in open-source that way, IMO.