I am conflating things in my mind a bit because most of the comments on my own videos that complain about sponsors or other revenue options use the "not as passionate" argument alongside the idea of "Youtube should just be a hobby". My apologies if that came off wrong. But it is inevitable that anyone making videos that is successful will have to treat it as a business because it is work.

Applied Science is a good example of someone who has not gone the sponsor route. He is crowd funded and has a Patreon page that is setup to charge when he releases a video(I'm a patron of his actually). It is still work to make the videos and describe what he's doing and how it works. He could be sponsored, even relevantly, if for example he used a Rigol scope to show something and then talked about it for a bit. But that wouldn't mean he is any less passionate about what he is doing.

The musicians and artists example is different though. Their hobbies produce media as an end result. Publishing it is part of the process. I make videos about vintage computers. My hobby without youtube would just be me sitting alone in a room tinkering. Creating a video out of whatever I'm doing requires deliberate additional effort.