At this point I'm less worried about covid and more worried about the global rise in authoritarian trends.
So you say that at some stage there will be vaccines for COVID-19 that are not nMRA (Pfizer, Moderna) or Viral vector (AstraZeneca)
Why? The people who are happy with vaccines are fairly happy with these vaccines and might refine them, but not about to dump them entirely for a different technique. in fact mRNA vaccines are the new hot thing.
And the people who really aren't happy with these vaccines, will never be happy. They'll find a way to object.
So what's the incentive for such a classical vaccine? Who's going to root for it?
Moderna and Pfizer (1) and AstraZeneca (2) are getting ready for the next round, still using their current technologies. They're not planning on going back to "classical vaccines" for COVID-19.
1) https://fortune.com/2021/11/29/covid-19-omicron-vaccine-prot...
2) https://www.independent.co.uk/news/uk/omicron-oxford-covid-a...
The mRNA technology would let us inject omicron-specific boosters tomorrow, but then there is a lot of other safety hurdles that have to be met before it gets authorized and then distribution hurdles to convince people to take it…
Mathematically, we will get to R=1 this way, some day or another, with some percentage of people getting it via illness and some via vaccination. The choice is still ours on how and when.