It started getting popular years ago and that’s when me an my friends switched to it too (back when I didn’t know shit about privacy). You gotta keep in mind the alternatives back then were Skype, which was meant for 1 to 1 calls, had shit audio quality and issues all the time and TeamSpeak, which was complicated because you needed a server (we were kids, we only knew what a server was from Minecraft) and had a text chat that was only a small part of the bottom of the window that was full of connected and disconnected messages, so I actually didn’t even know you could write in that. TeamSpeak’s interface also isn’t exactly good-looking or very intuitive. Then came Discord, you could create a server for you and your friends for free, you saw who of your friends was online and playing what, you could see when someone was in a voice channel and could just join, you had multiple text chats where you could easily send a link or memes while playing and you could easily share your screen with the others. It was a major improvement over the other two. I know that it sucks from a privacy standpoint but there’s good reasons why people started using it.

That’s what I’m doing. I have selfhosted E-Mail with YunoHost and send it through SMTP2Go.

Why does it matter where it’s based?

It would also stop most regular users from signing up. This kind of stuff being free has just become the norm.