The question is are unvaccinated Americans the ones being infected by the Delta Variant and if so, how severe is the infection?
It is mostly the unvaccinated but the vaccinated can get it too, in smaller numbers. It is not more severe than the other types.
The danger is that the high contagiousness can cause the heath systems in heavily populated areas to be in danger of overload again.
The most likely scenario is the “delta variant” doesn’t exist.
How many unvaccinated people have actually had covid and had minimal or no symptons?