Vaccine enthusiasts are utterly obsessed with titers. No, not that kind! But one can be mistaken. The vaccine enthusiasts certainly pursue the antibody titer argument with a single-minded obsession rarely seen outside of juvenile males. Antibody Titers
Are there any side effects of 'natural immunity'?
The worst side effect seems to be the inability to fly internationally
But usually passes in under 2 weeks
Lower profits
Not for companies selling ventilators, antivirals etc.