Yes. That is understoodThe herd immunity approach has many shortcomings. One of them is that, even putting mutations aside, the doctors don’t know if prior infection brings about any meaningful immunity. I asked that very question today to someone I know who had COVID back in April. He asked his doctors (some of the best) and they just don’t know, although it seems dubious. Herd immunity can only occur if prior infection yields immunity, and that is far from clear.
Like a cold