Specifically, I value my life way more than most people do, and I value the costs of time/money/pain less than most people do. He seemed to have been assuming that I value these things in a similar way to most people.

How do you know? Because you do things like flossing every day? Healthcare economics quite frequently mean that a person prefers to pay more rather than less to signal to themselves that they do everything in their power to stay alive.

People quite frequently make bad health decisions because buying an expensive treatment feels like they do something to stay healthy will it's much more difficult emotionally to do nothing.