In other words, a so-called "leaky vaccine" or a vaccine that lowers the chances of severe illness, but still allows for transmission of a virus, can create conditions that promote the evolution of more virulent pathogens.
For further reading here is a 2015 NIH-funded study that found "imperfect vaccination can enhance the transmission of highly virulent pathogens.". https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4516275/
The chart entitled "genomic epidemiology of novel coronavirus" shows the increase in mutations after the introduction of these leaky vaccines at the beginning of the year.
Was going to link what OP already linked.
The "vaccines" are causing evolutionary pressure which results in more genomic diversity. Meaning they increase the chance that new strains of fucking anything become more resistant. In other words, the vaccines select mutants and cause them to be sustained in the population due to higher fitness.
I understand the sentiment of "never been isolated". I haven't done my due diligence PROPERLY on that - but what the above means is that ANY fucking virus will evolve..
No matter what - it's bad news.
Already seeing it in Israel. https://www.medrxiv.org/content/10.1101/2021.07.29.21261317v1.full.pdf