Spacebar.chat is a really easy one to join that I found. And it's really a straight clone of Discord but without all the crap. It's decentralized so you can self host or join and instance and start your own "server" on there.

You don't have to understand any of that to use. It just works and looks like Discord.

i haven't seen anyone talking about it but i started testing out root app and i think it could easily drop in replace my friends discord. you can even import a discord server template with all your channels and roles.