Oh I never said anywhere could be safely opened back up- that's a leap. I say quite the opposite- people should be careful and not open schools until cases drop to near zero.
If the herd can't resume regular herd behavior without risking widespread infection, does it have immunity at all?
Eventually we will be able to but cases should drop further. Herd immunity doesn't mean zero spread, it means R<1 and dropping cases that will eventually become close to zero.