No, it means that to avoid the situation you just subscribed YouTube forced everyone to agree to be on the subscription plan or they'd effectively be kicked off of YouTube
If I were a content producer, I don't think I'd like that policy, but as a consumer, it makes the service more usable, since I know that anything I can see on the ad-supported Youtube site would be available on the paid site.
Much better than the model that cable TV uses where when I look at the channel guide I can see all of the channels, including the ones that I haven't subscribed to, and it's not until I try to watch a show on one of them that I discover that I can't see it.