This is an excellent technical point. Trouble is we already know that we are 'a few mutations away' from a covid variant evading vaccines, which is 'likely' to emerge. A recent Japanese preprint nailed it down to just 4: K417N, N439K, E484K and N501Y.
https://www.deseret.com/coronavirus/2021/8/26/22642809/delta...
https://www.biorxiv.org/content/10.1101/2021.08.22.457114v1
Rachel Walensky, CDC boss, July 2021: "the largest concern that we in public health and science are worried about is that the virus…[becomes] a very transmissible virus that has the potential to evade our vaccines in terms of how it protects us from severe disease and death". A new, more elusive variant could be "just a few mutations away," she said.
https://www.webmd.com/vaccines/covid-19-vaccine/news/2021073...
Albert Bourla, Pfizer CEO, Aug 2021: "Every time that a variant appears in the world, our scientists are getting their hands around it. And they are researching to see if this variant can escape the protection of our vaccine. We haven't identified any yet, but we believe that it is likely that one day, one of them will emerge."
https://www.insider.com/pfizer-ceo-vaccine-resistant-coronav...
Nature, March 2021: "Our study and the new clinical trial data show that the virus is traveling in a direction that is causing it to escape from our current vaccines and therapies that are directed against the viral spike,” says Ho, the director of the Aaron Diamond AIDS Research Center and the Clyde’56 and Helen Wu Professor of Medicine at Columbia University Vagelos College of Physicians and Surgeons.
https://www.cuimc.columbia.edu/news/new-study-coronavirus-va...
https://www.nature.com/articles/s41586-021-03398-2
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> long term immunity is maintained via memory B cells because constantly producing antibodies to every disease encountered is untenable
You are reading this backwards. I am not making any claims of what the appropriate level of antibodies ought be for long term immunity. I find "using tainted data we found 2x increase of antibody levels in post-infection + vax compared to just post-infection" studies ridiculous. The people pushing vaccines on people with prior infection, the people pushing boosters, the cottage industry of antigen studies making bold immunity extrapolations are making such claims. Perhaps you should spend some time educating them of basic immune system functions?
I wouldn't mind that much, everybody is free to chose their own risk profile. Right? Then they throw away the democratic norms and practices of past 200 years because they don't get the buyin levels (100%) they were hoping for. That is evil.
Antibodies are part of the adaptive immune system but are only produced when the body thinks there is an active infection. To simply greatly long term immunity is maintained via memory B cells because constantly producing antibodies to every disease encountered is untenable. https://en.wikipedia.org/wiki/Memory_B_cell
> grand total of 1 protein
That’s not how these vaccines work. A vaccination covers a huge range of mutations in that spike protein as the immune system memorizes multiple targets. Again simplifying it’s like memorizing 4 of your ten fingerprints, lose a finger and you still match the other 3. The protein target is chosen because it is part of the mechanism of infection, without that a simple COVID variant can’t infect you. Of course given enough time it could evolve around this issue but we are not talking about a single mutation.