I haven't given Discord a dime from the start because I knew this was going to happen.

The entire premise of Discord's free service was to gobble up the market from TeamSpeak, Ventrillo, and Mumble and capture the ecosystem using a ton of venture capital. In any sane world it would be an illegal mode of operation to provide "free service" based on venture capital like that.

TeamSpeak did manage to react but their reaction has been slow (I think they're a much smaller team and still a private company). Their new client is fairly feature complete but still not out of beta (AFAIK).

Mumble is an open source project and is still ticking as a result as well (though obviously it's received much less love since Discord stole the spotlight).

If I'm not mistaken, they are a private company.

Granted, they're a private company with a goal of getting an IPO soon, though.

Revenue is not the same as income. Maintaining cross-platform apps and hosting nearly a decade of messages and media attachments is gonna eat into that. Also, Discord is in fact a private company.