Average users view the web raw, this will go totally unnoticed by >90% of users. If web-drm becomes a thing then it will be easy enough to block those sites and add them to the list of media that is morally acceptable to pirate.

The most valuable sites are already advertisement free. Anyone remaining who implements this standard just reduces their viewers. People will do without or other sites will offer an alternative. The tech is doomed to fail because the consumer is always right.