I think while this may not apply to a small minority of streamers (certainly only a tiny minority of successful ones), it can useful to think of most streamers

I think while this may not apply to a small minority of streamers (certainly only a tiny minority of successful ones), it can useful to think of most streamers as a form of sex workers. While not engaging in strictly sexual activity for money, their job is to perform (non-sexual) intimacy in order to foster parasocial relationships because this is how they get paid. This is more obvious with those typically disparaged as "boobie streamers" but it equally applies to men or more "modestly" clad women. And above all, sex work is emotional labor. While for literal prostitutes the bare minimum can be entirely mechanical, even then it requires a certain level of performative (emotional) intimacy. The more abstract the sex work is (dancing, cam shows, financial domination, etc) this aspect remains the same and it is exhausting work that can take a serious toll. In a way it's more mentally exhausting than other forms of work because it requires a constant denial of one's self in order to perform as an abstract fantasy desired by those who pay for it. I'd even go so far as to say that all service work (especially in US-style "the customer is always right" jobs that penalize employees for "not smiling enough") is part of this spectrum and in many cases even non-service work involves performing this role towards the owner of the company or upper management (after all, every company wants to hire prospects who are "enthusiastic about the product" or "fanatic about delivering user experience" or other nonsense claims that signify loyalty and submission). This is also why so many streamers fail: if you want to be a gaming streamer or a politics streamer or a beauty streamer or whatever, fine, but being good at the thing (gaming, politics, makeup) isn't enough. The core skill you must build is engaging, building and handling an audience. This skill is absolutely transferrable (unlike, say, being really good at Counter Strike, unless you want to switch tracks to professional gaming) but it's far less well-understood and much harder to judge as an amateur. Some streamers seemingly just "luck into" popularity but they still end up having to either learn or hire someone to do "community management" and "moderation" and even then their popularity hinges on their ability to perform the character that made them popular and failing to evolve OR maintain that character can mean sudden death.