Messaging is broken.
Signal is centralized.
SimpleX doesn't do groups well.
Session doesn't auto-rotate keys.
XMPP lacks multi-device support.
And Matrix leaks metadata & is slow.
Nostr DMs are currently horrible. But White Noise looks like a promising potential upcoming solution to all of these problems. It uses MLS for the actual encryption with Nostr keys just for identity.
MLS is able to offer easy scaling for groups, that isn't bogged down by being a bunch of one-on-ones in disguise as a group UI, the way signal, session, and simplex are. Check out, https://www.whitenoise.chat/
Another promosing one is nostr:npub1h0uj825jgcr9lzxyp37ehasuenq070707pj63je07n8mkcsg3u0qnsrwx8 here's how they differ: