They are pretending to base it on science, when it is just another political opinion.
Calculations on what, exactly? There are calculations done on how police brutality and systemtic racism contribute to decreased quality of life for black americans. It's considered widely acknowledged within the healthcare industry that black americans have statistically significant health disparities compared to other races, and that additionally it is statistically known that the covid19 shut down primarily affect the service industry, which hits people of color disproportionately towards white people (as people of color are less likely to have jobs that can be worked from home).
But you'd also have to do the same for the 3 months they've taken from everyone else due to lockdowns.
Until they do that sort of thing, its politics not a social science.