How recent is that? More than a decade ago, my friend related to me how his grandmother was subscribed to cable TV through comcast, but one channel wasn't working.

And every day, she'd call them to complain about the one channel that didn't work, and they'd apply a minor credit to her bill.

As far as I'm aware the "self-service" version of it on their website is in the past year. I think you're right that it's been possible over the phone for a long time though.