If this is the analogy, why doesn't Google try something like protecting from sticks in the first place? For example, they could lock all of YouTube behind a login & paywall.

It seems like YouTube is attempting to FORCE people to adhere to its desired business model. If ad-supported video playback is not economically viable, then maybe it's time for a new model to be born? There is no obligation for me to pick up the stick and hit myself with it because Google says I should. I downloaded a bunch of bits that Google sent to my computer, and then I read the bits I cared about. That's how every webpage has worked in my experience.