They wouldn't be there if they were susceptible to ditching bluesky, but for Nostr, I'd focus on the Other Stuff that makes it more than a "social media protocol".

Long-form, communities, lists, dvms, E2EE chats lime keychat 0xchat & otgers, focus on "ease of data sovereignty"

NWC is simple af, enables zapping which is a major value prop, but from the outside it seems like magic.

Bunkers are basically decentralized 2FA we're all used to; load up a nostr app anywhere, scan a QR once, and you'll get push notifications to your phone going forward to approve. We all (should) use 2FA; nostr has it.

Most ecosystem components like that are interchangeable with other or newer forks or projects.

The developer community are incredibly focused & active on tge platform.

etc.

(Admittedly, I'm not caught up on bluesky's value prop)