I've been using both for a while now, here's my take.

Community-wise neither are exactly my taste. Nostr is zealous leaning bitcoiners, while FC is degen leaning ethereans. Both have small pockets of actual normal people which are great. I don't post much, but my content happens to get much more engagement on nostr. I'm not sure if this is simply an audience preference or a protocol discoverability issue (eg high spam & priority mode on FC)

Tech-wise there are trade-offs. FC uses a logical singleton which means it's forced to play the balancing act we are so familiar with when using blockchains: scale vs decentralization. Nostr bypasses this entirely but instead has to find solutions for fragmentation. If not addressed this manifests as "missing" notes and slow to compute follower/like counts.

If I were to engineer a network myself, it would look similar to nostr's relay design, but with a DHT (something like pkarr) for solving fragmentation - in a similar way DNS solves the internets fragmentation

Pubky looks to be exactly the architecture I was thinking of here. Will be watching this project closely.

Pubky looks to be exactly the architecture I was thinking of here. Will be watching this project closely.

https://pubky.org/