I received 2 pfizer shots last dec and january at the hospital where I work. In August, I checked my antibody level to the spike protein and they were barely abnormal (I know not a great test for immunity).
So I got revaccinated with two doses of Moderna in late august and mid September at CVS. It is about all I can do to avoid serious Covid infection. We have mandatory masks at the hospital.
Delta will help with herd immunity, killing some of the unvaccinated and making many others immune at least to the delta variant.
Interestingly, near the end of life, some of the unvaccinated are remorseful and wish they had gotten vaccinated while others still firmly deny the existence of Covid.