> YouTube is a bit less clear: it doesn't really have any competitors, and is extremely popular and widespread, but it surely costs a fortune to keep running.

There was a brief moment when it looked like Twitch would kill YouTube; then, much like Instagram responding to SnapChat, they took the best parts of it and added them to itself. I'd be amazed if YouTube wasn't profitable now with the combination of more ads, more subscription/superchat options and the pandemic-era boom in streaming.