Slackware '90s gang representing:)
Anyway, I mostly agree with you. I think all those areas can be improved. Where I slightly disagree is the idea that most of them want to self host. The irony of the thing is that it probably will take a large central entity (or two) to take it mainstream. Someone to handle all the faffing about that comes with hosting. Time spent that big-time creators would rather spend on production.
Or maybe it's fine the way it is. Maybe YouTube etc is where the big-time players remain and Peertube becomes the Geocities for video. I'm fine with that. I want my old web back with small sites and niche interests hosted by enthusiasts. I really don't know.