The guy who he was talking to works for Comcast, is pursuing Comcast goals (which aggressively punishes agents who don't have high enough retention rates), and is recorded and often monitored by Comcast. The Comcast agent clearly has a list of complaints/responses that they use to try to defuse all complaints -- not that they've actually solved your problem, but rather that they made you think the call was no longer worth it and just give up trying to cancel.
Their entire job as retention agents is to waste enough of your time, and try to press enough buttons, that you give up.
The whole "I am waiting for the system to complete the process, so listen to my arguments while we wait" nonsense, for instance. Credit card companies do the same thing for activations, using the "waiting for the system to finish" to pitch insurance and other unwanted products.
This is a problem. This is a major problem. This is why so many services allow you to sign up in seconds online, but require long, drawn out waste-of-time phone calls to cancel. To force you through this gauntlet, making most just forget about it.
Cynically claiming that this guy manufactured this situation betrays logic of this situation. He dealt with what is a profound problem that most customers deal with.