I think it's interesting what was posted above re: popular streamers and evangelist cult types. I've never really gotten into Twitch other than the occasional look at some of @murray Resident Evil 2 content. I find watching FPS games gives me instant motion sickness so I tend to avoid.
But back to the evangelical slant; I see similar things with YouTubers within the design community where someone builds up a channel, offers insights into their workflow has known heads on within the design community and like clockwork a few months later they monetarise the shit out of it with exclusive content. Partly this is giving away stuff but I think it's a bit like PS4 Pro and video card branding... OMG you must be the real deal because you are part of this inner sanctum. Look at your exclusive <insert brand here> t-shirt you posted on Instagram. What I find is within the design world is these cults appear to be large yet you ask anyone in the real* design world and nobody has a scooby who these people are. It's all smoke and mirrors and cult of personality.
* Grafting, working designers rather than bedroom aspirational types hitting up Dribbble.