It's extremely context-dependent in other ways as well. For example, I get this with my brother and used to get it with my mother on the phone but not otherwise

It's extremely context-dependent in other ways as well. For example, I get this with my brother and used to get it with my mother on the phone but not otherwise. They just hate to hang up. And yes, it became truly comical on calls between the two of them. I get a similar thing in online chats with most people. I get it with my wife, in person, on certain topics but not otherwise. If she starts talking about COVID statistics, I know I'm stuck for at least ten minutes unless I'm willing to have her pissed at me the rest of the day for cutting it short. Topic, medium, relationship, and even external context all affect this. The question I would ask here is: why would we expect people to want to end a conversation at the same time? The article presents this as some sort of failed communication, but maybe an exact match is just naturally unlikely.