So, this is the study I am working from: https://www.nature.com/articles/s41586-021-03738-2
The one you cited appears to be a preprint.
This study shows that antibodies elicited by mRNA-1273 (Moderna) persisted for at least six months. https://www.nejm.org/doi/full/10.1056/nejmc2103916
Both of the studies I’m citing here have in fact been published and I can’t find the other one in published form.
Those countries had governments willing to compensate restaurants instead of just letting them go out of business, are smaller without large land borders. (New Zealand had a particularly easy job), and the fact that Vietnam is now seeing a surge (just using them as an example) is actually proof of my point: That unless we eliminate the virus everywhere it will just come back.
I never said people shouldn’t wear masks. I said that our government will not provide the required compensation to keep another shut down of indoor dining from resulting in many restaurants going out of business. You’ve SEEN how we’ve had to fight tooth and nail for tiny crumbs that the right wing don’t want to give us.
Oh, and then there’s the fact that some people will literally kill in this country to avoid having to wear a mask.
The capability might be present. The political will is not.