The worst by Denocide by percentage of and Country was Cambodia from the Satanic Pol Pot.
Communism kills. In terms of sheer numbers, hard to beat the old USSR and China for democide:
https://www.hawaii.edu/powerkills/20TH.HTM
Covid killed just under 7 million people worldwide as estimated here:
https://www.worldometers.info/coronavirus/coronavirus-death-toll/
So, even if you believe Covid was democide, the headline is a lie.