SCOTUS never really addressed this. The majority opinion was basically just a bunch of vague hand-waving that amounted to "if it looks like a duck...".

That was one of the most frustrating things for me when the decision came out. Obviously we all understood that we might lose, but to have a decision handed down that was so completely devoid of any sort of definitive logic or reasoning was really, really demoralizing.

They effectively just said "You look like a cable company, and even though we accept that legally you are most certainly not a cable company, we still find that you publicly perform... because cable companies publicly perform".