I'm not an expert on advertising, but I suspect these concerns are often overblown. There are YouTubers who get demonetized--presumably because their content isn't "advertiser-friendly"--who still manage to get individual sponsorship deals. If these companies were serious about being a "common carrier", they would invest more money into developing an advertising market where advertisers could pick and choose the content they wanted to advertise and less money into demonetization.