Even video game streams I have trouble understanding (but I respect there is elements of skill and strategy,) but slots? Just not for me (if giving money to people to put in a slot machine is entertainment for you, I have nothing against it, just not for me.) To me this makes sense in the context of content that involved a lot of time and effort to produce (IE Youtubers who make in-depth history documentaries on their own.) This makes no sense to me in terms of watching somebody stream themselves hitting max bet at a slot machines for 20 mins (often with minimal commentary.) But, apparently slot streams are super hot right now, so there must be something to it.
People donate to Youtube channels to help produce content that they like.