I can’t see that Parsons is doing anything rude. He doesn’t say that he is abrupt or unfriendly with the person when he tells them they have 30 seconds. He doesn’t say that he rushes the customer off the phone - to the contrary, he says he listens to the problem, then gets the info he needs to deal with it.

Lastly, he doesn’t say that he never returns voice mail messages. He doesn’t return messages from people who don’t say what they want.

I’ve been following the same rules for years.

I spent two days as a telemarketer, enough time to learn that the quicker you hang up on them the better off they are. They are forbidden to hang up on you: as long as you keep the conversation going, they are obliged to counter every argument you say. If they do not get a firm no they have to keep talking to you. The nicest thing you can do to a telemarketer is hang up on them as soon as you realize you will not be buying what they are offering. They will be just as happy if you do not waste the seconds to tell them what you are doing, either.