“Keep in mind natural immunity will prompt mutations as well.”
Yes, that’s why viruses are different now than they were 100 years ago, or even a couple of years ago. But natural immunity militates against the whole virus, and potentially recognize multiple surface features that are unique to it. The more of those features there are, the less likely a mutation would be present that lacks all of them.
The vaccines for Covid all focus on just the spike protein, and, I think, just a single epitope on it. That makes it more likely for a mutation to emerge that evades the immune response.
Totally predicted by vax experts (not working for vax companies) last year...shocking.