It runs in a browser shell. It's got WebRTC ready to go. The hardest part of WebRTC is dealing with whatever bullshit Mozilla and Apple are doing this week, so given that browser shell is Chrome, and you can hardly walk through a computer science journal without tripping over a consensus algorithm paper these days, it's really not that complex.
To be fair, this is a really complex feature to add, so it would be a serious commitment from JetBrains to build it.