Normal people do care about their privacy, they just don’t know enough about tech to understand what services to use—which is why they trust the surface level privacy marketing from Apple. But if you are someone that does understand the tech, then you should feel empowered to help these folks out on their messaging front. If you host it & give them accounts, many come. You could set up an XMPP server for messaging & a Mumble server for voice coms & folks will be happy to chat with you regardless. My longer-term experience is folks are happy wdth how much lighter weight these 10±year-old technologies are that they start to prefer it.