I'm not going to address your non-sequitur about immunology as this would involve a graduate course molecular immunology, but I'll speak to a couple points:
With respect to people vaccinated being asymptomatic spreaders, the answer is "no" for 99.5% of people vaccinated. If you read the NEJM journal article, it demonstrated with statistical rigor that the no. of people vaccinated that subsequently became infected was only 0.05%. If you're not infected, you can't be an asympomatic spreader.
I haven't seen any sequences that would define a new, genetically-curated SARS-CoV type from SPHERES* or the nor the Genomics UK consortium that would define a COVID-20, COVID-21 , yet. If you do, please forward as I am tracking the sequencing of new variants.
I fully expect there will be round of booster vaccinations that will become available later in 2021 comprised of a multivalent vaccine for the UK, SA, NY, and CA variants. If so, that will be great, as will it signifcantly curtail the spread of existing and origination of yet new variants. If so, I'll get that vaccine as well. The process is easy and fast.
This is virtually no different than the multivalent influenza vaccines that are administered yearly.
Bottom-line? Vaccines work. This is why you are not at risk for getting smallpox or polio. Those diseases have been effectively eradicated by vaccines.
*– CDC consortium for SARS-CoV-2 Sequencing for Public Health Emergency Response, Epidemiology and Surveillance