Thank you for this, very helpful. What I don't understand is details around how and when the mutations would actually (if ever) stop?

Or at least mutate in a non-incredibly life threatening way such as the flu (albeit a very different virus).

We seem to not talk about herd immunity anymore. So if everyone in the world was either vaccinated and/or had antibodies from previous infection, would the virus stop mutation?

With many Asian countries having zero-tolerance policies, if and when those countires open up to pre-covid levels, is that just 1/6th of the world that would be new hosts for the virus to infect and mutate again?

I hope these questions from a nonscientist make sense!