In addition, the vaccines currently in use -- at least in the West -- are either mRNA or vector vaccines containing only parts of the virus (as far as I know only the spike protein from the virus's surface). I would expect them to result in a more specific immunity which is easier for the virus to circumvent, my mutating only its spike protein. Conventional vaccines however, which are more prevalent in the developing world, as well as having gone through COVID, should provide a broader immunity - at least in my half-educated view.