Yeah, xmpp is a great protocol, but everyone needs to be in the vicinity of the server. A mesh network (p2p) where every client also relays messages for other clients is better suited for this usecase. I think meshtastic is an open standard for this. Briar is a valid alternative that works with phones, which most people already own. Not the greatest idea to bring those to protests, though because of network surveillance attacks by police forces. A meshtastic device would solve this problem.

I wish Snikket could work on Yunohost! 😢 I have a core i5-10500T and 32G

Well yunohost seems to support prosody, that should work very well. Snikket is basically just prosody with some extensions preinstalled. If you want an xmpp server on yunohost you could just install prosody or alternatively run snikket in a docker container. Prosody might even be easier to setup if you can install it via the yunohost gui.

I still love getting messages via xmpp from friends and family using my own snikket/ejabberd instances after years of use. Calls as well.

Video conferences via jitsi meet fill my heart with joy since the covid epidemic. These are also xmpp based. It’s just a cool lightweight protocol.