Particularly that last point. I've tried setting up blocking for my friends / relatives, just a simple uBO setup in the browser - their main concern is what happens when it breaks the page or doesn't work. I've explained to them how they can disable it for that page or report a filter list issue, but they just don't seem to "get it" and usually end up uninstalling the blocker. I think to get mainstream a service would have to provide technical support on the grandma-can-barely-click-the-mouse level.

I do think though that people can understand the benefits of adblocking. For example the digital video recorders that cut ads out of broadcasts, that was/is a successful product. And my friends complain about the ads - it is just that the blockers are not at a level where they can use them.