Youtube seems to me to be on the edge of a cliff. They are allowing advertisers to call all of the shots. You see videos all the time about how "Trending" tab or whatever other recommendation section on Youtube favours established/mainstream content. The reason is that brand friendliness is make-or-break for Youtube. If a big enough advertiser complains their ads are in front of CreatorZeke's videos then Youtube is going to do whatever necessary to appease the million dollar spender. That has a chilling effect across the platform as creators divine what kind of content gets the sweet ad $$$.
On Twitch, in comparison, some of the biggest creators don't even show ads. They exist very well on subscriptions and donations. This greatly reduces the effect advertisers have over shaping the content that is created. I think fans are starting to realize this and it will likely continue to generate a sense of freedom on Twitch when compared to Youtube.
It reminds me of the "100 True Fans" article on a16z [1]. It is reasonable for a creator to exist and thrive with 100 to 1000 devoted fans.