Something surprising I learned a while ago is that one of cable tv's selling points used to be no ads.

This is one of those urban myths that refuses to die. I've looked for the supporting evidence and can find none. When we got cable as a kid in the 70s, that was certainly not the selling point. Cable was used by remote communities that were out of range of the broadcast signal. The only channels that existed at the time (i.e. ABC, NBC, CBS) all had adverts.