That's exactly what I was thinking. As a producer of content, if a specific app is denying you an income, why would you not just block it.

Sure, you're turning away customers, but you're turning away customers that aren't paying.

Blocking would work for about five minutes, until someone releases a user agent spoofing plugin for Safari, just like the one that already exists on Firefox.

It exists under the Develop menu in Safari already. Also, there's no way Apple is going to do this, it's preposterous.