So it doesn't cover all ads. Sponsored content is advertising. If youtube premium doesn't result in creators making enough to support themselves then it's feeding youtube for no net gain.
Any "pay for youtube directly" strategy MUST result in a creator 1) not needing to get external revenue from merch, sponsors, patreon, or anything like that. 2) not be so at the mercy of youtube algorithms and unaccountable decision trees that content match them to silence, remove their payment through "demonitization", and provide actual support to the creators so they can focus on creating instead of whipping up public shitstorms just to get basic support, and 3) reward creators for making higher quality content, instead of more addictive or "engaging" content.
Right now Youtube Premium isn't that service. What is that service? Floatplane and nebula are trying to be that service. Nebula specifically has nearly every high quality, "tech, science, invention, discovery, learning etc" content creators and it's like $100 a year. All of my favorite content creators are part of it.