In a sense, it's selfish if people in the critical categories don't isolate (tough as that is going to be for some of them) because it means more critical care beds will end up being taken.
My Dad is enjoying a week at the seaside since he's been cooped up for a month because of the weather. I'm loving this idea that he can be told to self-isolate for a further few weeks or months. I'll give you his number if you like and you can tell him.