Only the vaccinated will preferentially evolve variants that are resistant to the vaccine. The vaccines are leaky, as evidenced by the recent outbreak in the Northeast. A saner strategy with leaky vaccines is to vaccinate the small population that is vulnerable and let the rest of the population of develop a natural herd immunity. Otherwise you are creating a fitness advantage to resistant strains.
This is not how it works, and "natural" herd immunity has never been a real concept in epidemiology - which it is clear you are speculating on without bothering to read about but should also be trivially obvious from the fact that until vaccines none of the vaccine preventable diseases ever went extinct on their own.
> Herd immunity is a form of indirect protection from infectious disease that can occur with some diseases when a sufficient percentage of a population has become immune to an infection, whether through vaccination or previous infections, thereby reducing the likelihood of infection for individuals who lack immunity.
Yes, and wikipedia is not the study of epidemiology.
Epidemiology as a field did not publish papers or study the idea of "natural" herd immunity till last year when politicians started throwing the term around and a whole lot of researcher's scrambled to see whether this insanity had any merit.
Of which the answer is what we already knew just spelled out more specifically: no, this doesn't actually happen in the wild without vaccines, because it's literally just spreading the virus. Viruses burn themselves out after infecting basically everyone, provided immunity is long lasting.
It is misleading though, since this definition is merely ‘flattening the curve’ for the rest of human life, and accepting the increased death rate every year. By contrast, a successful vaccination effort also ‘flattens the curve,’ but additionally substantially reduces the rate of deaths. The latter is what we have observed happen with high confidence in the vaccinated population for COVID: deaths of vaccinated individuals is much less common than for unvaccinated (back of napkin math seems to currently be somewhere between 100-1000 to 1 across most age ranges)
I don't think when people talked about herd immunity they meant that the coronavirus would be wiped out, just that it'd get the replication rate down to a manageable level. Just like those diseases that vaccines wiped out, the young would always be at risk of being infected. In this case though, the young (babies excepted) are also fairly protected from it getting serious.
Given enough time, a virus will tend evolve to become more infectious period.
Somebody else could confirm this, but it seems to me that the current known variants of concern are not responses to vaccination.