Because Discord is so extremely easy to set up and get going. In the past, we either used skype, or one of us would set up a mumble server, but Skype has gone t

Because Discord is so extremely easy to set up and get going. In the past, we either used skype, or one of us would set up a mumble server, but Skype has gone to complete shit lately (like, oh, you can't make a group call if there are more than 20 people in the room, even if most of them aren't online) and mumble requires devops-level skills to set up. Discord, in comparison, is just "download this file, click new server, done". I do feel disgust about how it's a hundred megabytes of a bundled browser with mountains of javascript, but it works so much better than anything else. And it works on Linux and Mac just as well as it does on Windows, which is more than you can say for Skype. If it ever also gets P2P file transfer, it would be the absolute undisputed best chat program in existence.