As of 2 January 2022:
For the world:
( 5,440,715 “global deaths) / 7,917,528,778 global population ) x 100 = 0.0687%
Less than seven one-hunredths of one percent “global deaths” from Covid over two years.
For the US....
( 825,819 “U.S. Deaths” over two years / 331,002,651 U.S. population ) x 100 = 0.249%
About 25 one-hunredths of one percent, given the rule of thumb that about one percent of a population dies off each year.
Now try out your 80-year medieval plague numerical analysis again.
I had cause to spend time some years ago studying logistical impact of rattus rattus and rattus norvegicus. You would be unwise to hitch your wagon to your bizarre imagined gotcha of a handful of years.
The Yuan Dynasty was called that by Kublai Khan circa 1290ish. He then died and his son took over. Plague arrived in the 1330s. Your superficial wiki look did not lead you to what happened to the dynasty over a fifty year sequence of acute absence of farming personnel.
Plague killed society via starvation. The mechanism of starvation death is rarely a calorie deficit that creates too few such to power lungs or heart. It is much more a failed immune system that permits opportunistic infection.
Plague persisted for decades because of the synergies of food. Rattus Rattus appeared when there was food for it to eat. Killed the farmers that created it, often before any children could be taught farming.
Decades upon decades this went on in the dynasty. Its roots were the Mongol Empire. Sieges of expansion were ended as often by food lack as by the disease in the surrounding army.
The Hundred Years War persisted because of plague.
About 10 yrs ago some uncomfortable analysis unfolded concerning transportation speed of that time in both China and Europe. It led to suspicion Y. Pestis was not the agent. This ended with DNA analysis of bodies in graves, but there was never a rebuttal to the speed issue.
You have a few years of reading to do. I’ll wait.