It has become pretty popular. It has even swept away a fraction of IRC users, which is no small feat.

I personally don't like it for various reasons, and would suggest Teamspeak for your use case.
https://www.teamspeak.com/en/It's much cleaner and safer IMO. Both Discord and Teamspeak have proprietary licenses, but those are pretty liberal for individuals and small teams. I just would trust Teamspeak much more. Also, last I tried Discord, the app was much more ressource-hungry.
Just my opinion.