It's already been demonstrated that the Covid-19 has mutated into becoming more easily transmissible. Perhaps there may be some scientific basis or physiological connection between being more transmissible and being less potent? Perhaps a stronger initial shock fires up the immune system to create a stronger herd immunity. This seems to have happened before, but may not happen with Covid-19. It would be wishful thinking to rely on it for setting policy.

EDIT: This was making the rounds a week or so ago https://www.nytimes.com/2020/06/12/science/coronavirus-mutat...