Not to mention only available on certain phone brands and certain carriers (where I am, only one of major four).

I don’t like it at least because it’s Electron. I had better experiences with Nheko and Cinny.

My concern is that they’d demand not just profit, but growth. But I wonder if they’d be able to go on by charging for commercial use - hosting servers, tech support, etc

I didn’t personally have problems with reliability (same as for XMPP, Matrix however has broken for me a few times). As for multiple devices - I just use two, with identical names and profile pictures, one on laptop and one on phone.

XMPP

Selfhost able. But yeah, “decentralized” would be indeed a more fitting term.

“Everyone should be hosting a server” was NOT my point, sorry if I got misunderstood. My mother could in no way host an XMPP server on her own - but I could register her an account on mine.

Rather, I meant: a) if you can host it, suggest your friends and family to use your server; b) if you can’t - that is still better: with multiple public servers available, there is no single point of failure, you can choose a server in whatever jurisdiction you want, or even an onion/i2p one.

Moral of the story? Use selfhostable decentralized messaging instead.