I think it is a far gone conclusion that Pfizer can't achieve herd immunity. MSM now will move their goalpost from effectiveness against infections to effectiveness against hospitalizations. In the end of the day, Pfizer or any mRNA vaccines isn't that superior than traditional inactivated vaccines. mRNA vaccines trigger a higher load of antibodies to achieve a short effectiveness against infections. After the initial spike of antibodies wear off, mRNA vaccines effectiveness dropped dramatically especially after new variants emerge.