I haven't been able to get a straight answer to this even from scientists on science threads... Given the following: 1. Virus mutations do not directly react

I haven't been able to get a straight answer to this even from scientists on science threads... Given the following: 1. Virus mutations do not directly react to the vaccine. These are simply random mutations. 2. If a mutation occurs that has a higher probability of escaping an existing vaccine, then in one unvaccinated person, that mutation has an identical chance of occurring whether that person is part of a 0% vaccinated community, a 50% vaccinated community, or a 99% vaccinated community. 3. Natural selection just means its ability to reproduce. Let's say that the mutation can escape the vaccine at 100% probability. Then: Can that virus spread equally regardless of whether it's a 0% vaccinated community, a 50% vaccinated community, or a 99% vaccinated community? Because it sure sounds like people are saying that in that scenario, the mutation spreads less in a 0% community, and more in a 50% community. Are they saying that in a "mostly unvaccinated" community, the other variants (that the vaccine protects against) that are more prevalent somehow serve to "crowd out" the mutation? Because I don't know if that's true - at least, I've seen reports that suggest that people can catch more than one variant at one time.