[wpietri]

I don't think you can place the burden of evidence on one side alone. Enough people have experience with YouTube as users, creators, or both that it's not wild to think that many people have reasonable intuitions about why YouTube dominates the market.

And if we are going to demand evidence of critics, I think we should also demand evidence of promoters of things like this, who often seem guided by a Big Idea rather than any evidence of user needs or proven ability to solve those user needs.