Just to add to the many responses here with a simple quip on this issue (which I’m taking from one else)
The fediverse presumes people care more about independence than socialising. For most it’s the other way around.
IE: it’s about the socialising “stupid”.
Even for us techy types happy with the system here … it means we get to socialise with like minded people. The independence we have here is often secondary, I’d wager, to what we all get out of this.
It’s not BlueSky making the Reddit alternative, it’s third party devs. There are a few alternative apps being built on BlueSky architecture and ATProto right now.
And yea, it definitely could overtake and harm lemmy, if there are people here into the BlueSky approach (which likely suits Reddit-like apps, I think I’ve seen some say BlueSky has a Reddit flavour to it).
Honestly, given the dominance Mastodon has in AP and the shitty interop it has with lemmy, migrating to ATProto wouldn’t be the most insane idea for Lemmy IMO. Relying on BlurSky’s relay wouldn’t be for everyone. But some sort of multi-relay set up seems plausible and might be cool to see.