(Anonymous)Visitors is not a very useful or valuable metric. Blindly pumping content into the ether isn't going to convert to value, or cashflow.

I think we are seeing the advancing erosion of (generic)ad-supported free content and services. Which is not necessarily a Bad Thing.

If you can't be bothered to identify yourself with an account, then these services do not get much value from you, and many times see you as loss/overhead, so limiting access to their content is logical on their end.