Was he not around his family though? Presumably his wife gave birth in hospital less than a week before? Was it 'biosecure'?
I'm sure with the test and sensible behaviour all was fine, dropping Archer could be as much about punishing indiscipline (rightly so). Some of the things I've seen around the England team in the past few weeks doesn't sound like joined up behaviour though. For example players that have been in this biosecure bubble for a couple of weeks, presumably subject to tests, still had to eat their meals with social distancing. If they had been isolated in a biosecure bubble how could they have caught something and if there was a risk of this why were players not distancing on the field?!