RSS is around, but Google successfully relegated it to a grave yard, when they stopped supporting it in a big way. RSS is such a simple and powerful thing, it's a shame it's almost nonexistant. Even ActivityPub should've been "built around and on top of RSS" rather than as a separate thing. Same is true of Nostr. Nostr could've been an extension to RSS and let RSS be the least operative fallback for the entire protocol, but yet the format for all delivery nonetheless.

Completely agree! We already had a perfectly good protocol for content federation.

I've hosted an RSS feed on my blog for 20 years, in the vain hope that it is still being consumed by someone.

I think the only use case keeping RSS alive is podcast feeds.