Really, none of that matters too much. Comorbidities exist. They exist for the flu as well. Just because America being unhealthy contributes to the number of deaths doesn't change the deaths. The years of learning and vaccines aren't too relevant for the same reason. When we encountered this virus, there was no vaccine and we knew nothing. Over the next year or two, COVID will (or should unless a bunch of our gubment and corporate overlords try to use it for personal political gain) become no more interesting or relevant to us than the flu was prior to COVID. Now that there are vaccines that are widely available, this thing needs to go away as an issue. We are about six weeks away from the point where anybody dying from this thing is really bad luck or their own fault. Also, while not everyone who compares COVID to the flu (i.e. medical professional) is minimizing it, most people doing it on the bunker are doing it exactly for that reason.