I don't exactly know how it works but creators tend to call it "my streaming platform" and that feels a little bit like a marketing angle. For the longest time I thought Adam Neely had literally funded and built Nebula.
It is a marketing angle, Wendover Productions is the actual creator of the service and has a video about how they bootstrapped the service and got it to the size it is currently.
https://www.youtube.com/watch?v=Alqt6RCEWdM