So basically its Lemmy but better? I haven't been following Nostr development too much, it seemed in heavy development when I last peeked in about 6 months ago, the amount of devs and work being done is quite impressive though.
I think its inherently more federated because of how relays work. There isnt any potential for the instance blocking tribalism you see on The Mastodon Network™
Weather or not its Lemmy but better depends on your choice of client. They pick and choose what Nostr Implementation Proposals (NIPs) to put in their apps. So you could get comfortable on a client that doesnt even implement groups lol
They will work it out with time. Unlike AP the devs all like each other and work together