you can see with youtube premium that the value of individual ad views is basically nothing, and getting users to pay a reasonable monthly fee ends up being much more profitable. nobody will do the 'pay per video' thing because its not as profitable as just getting a monthly sub.
I wouldn't pay for each video I watch now, but I could probably watch less. It's like eating junk food now: you can eat nonstop but it doesn't nourish.
