While it is academically interesting to try to apportion blame between COVID-19 and underlying conditions, the basic fact on the ground is an anomalous rise in illnesses requiring critical care and resulting in death.

This has been true since the first alarm bells in China, and has spread to other nations in a way that is easily observed first-hand, clearly reported by front-line medical staff, and consistent with the spread of a new disease.

That obvious data is what populations and governments are reacting to, not some calculated IFR.