RW, unvaccinated people could just do the rest of the people a favor and keep out of museums on chol hamoed.
For those who had Covid, whether by act of G-d or by negligence, it is not enough to rely on that alone to conclude that you are not in danger or not a danger to others. Those who measure high antibody count have a stronger leg to stand on, but I am not sure what is percentage of people who 1) belong to the group of unvaccinated, 2) had Covid, and 3) continue monitoring their antibody level. (1) and (2) are mostly uneducated either very rural or very urban, while (3) presumes some
level of education. This might cover a section of Jewish community, but probably not the others.
That said, FDA & CDC will probably get to the issue of antibodies of covid survivors after it resolves all the other urgent issues – boosters for Moderna, J&J, vaccines for children, etc. These people sound a little overworked for now …