There are 4 servers on OVH channels at 10 Gbit/s, the video stream 5мбит/s 1080p 30fps, and at the peak when 3000 spectators, and channel download under 26Гбит/s, though, if you count on the calculator it comes out to just 15Гбит as well? Soon to be on 25000-50000 spectators, and not to buy with 50 servers? (on these servers, only the flow, the site and chat on separate servers)
1) not all speed ice and they don't want to watch in the best quality video. reduce the video quality(make the choice) and lower sound quality at least 128 KB/sec(no one will even notice)
2) Maybe You bad the traffic is distributed.
3) More people need more resources. Buy servers still have.