If 1 vaccinated person infects another say 3, but then those people fail to infect anyone else - then it doesn't actually matter what selective advantages that viral strain had - 100% of the virus has died out.
But if the same chain terminates in the vaccinated people then infecting an unvaccinated person...then the new mutation escapes and potentially becomes dominant within the reservoir (unvaccinated people) and a failure to spread through the vaccinated population doesn't lead to the destruction of the mutant strain.
the next question is what happens to those with acquired immunity, and why are they being forced to be vaccinated?
I see many studies that show that their levels of antibodies seem to be even better than ones from the vaccines.
Can you please explain more?
Why can't both hosts A and B both be vaccinated folks?
Is'nt there a 3rd category - those who have immunity via past infection? How do it work in that case?
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If what you say above is correct, then why do we see new strains in flu?
Has'nt pretty much every person on earth been exposed to flu or vaccinated against it?