Nothing costs anything for auth. What's expensive is storage and meaningful actions. In terms of "easy way to provide auth" … for who? Certainly not end users

Nothing costs anything for auth. What's expensive is storage and meaningful actions. In terms of "easy way to provide auth" … for who? Certainly not end users. Also, the people who want a "pay per use" web are, shockingly, generally people for whom "pay per use" is financially feasible. That is not the majority of people.