"Instead of being more active than the content, they should just replace it."
Why should they be videos? The presence of a video on the page does not suddenly wipe banner ads from existence, they can still be present.
Advertisers probably wouldn't pay nearly as much for banner ads - it's better than nothing, but probably not enough to support huge server costs and still give some money to the channels. I don't like watching video ads either, but I think it's a small price to pay for a good and free service - and almost all ads are skippable. It just sucks that some people feel that they are entitled to said service and can't take time out of their day to support it, and the cost (in terms of number of unskippable ads, for instance) falls to the rest of us. Yes, I could solve that by blacklisting YouTube, but then I'm no better, and if everyone did that YouTube would shut down.