But viewers don't want to have to be constantly bombarded with "encouragement" for superchats. It's a bad experience no different than an in-video sponsored read, or any other YouTube ad.
I don't disagree, and I wouldn't suggest a creator constantly bombard it. (However, that might be most effective, as constantly bombarding with "like and subscribe" seems to be, though personally for me I don't tend to watch channels that do that and for the random videos I do see where they do, it's often skipped by sponsorblock.) However I think if a creator wants to be honest with their viewers that they will stop creating unless they can receive $X across ads/premium/superchats/patreon/as many options as they can, rather than trying to bully them into thinking the only choices of support are an absurd premium fee to the platform or psychological self-harm by enabling ads, that is a good thing. As would be their decision to actually stop spending their time doing something that isn't worthwhile to them if they can't make it. Meanwhile other creators will happily go on creating high quality stuff for free because they don't care about making money that way, and youtube itself will be fine as even adblocking users, who also never directly monetize another way, contribute enough indirect revenue (user profiling, algorithm shaping, user growth, recommending...) to the rest of google's empire that it doesn't matter. (And if they do monetize ever with e.g. a single $5 superchat once in a blue moon, google's $1.50 cut of that, even after their expenses of payment processing, can make up for quite a lot of missed ad impressions.)