What are your thoughts on this study?
Since the onset of the COVID-19 pandemic, a concentrated research effort has been undertaken to elucidate risk factors underlying viral susceptibility and illness. Among these efforts, several recent studies have investigated the association between blood type and COVID-19 infection. Each of these reports provides important information with regard to understanding the underlying disease process. Although these reports might be inconsistent in their findings, certain trends are evident. Many studies report that blood type A might predispose one to increased susceptibility of infection with SARS-CoV-2, and type O and Rh-negative blood groups might be protective. Although this appears to be an emerging trend, the impact of blood type on clinical outcomes remains unclear. At this point in time, there does not appear to be any relationship between blood type and COVID-19–related severity of illness or mortality. Current literature does not support blood type as part of a predictive model of viral illness or mortality, and ABO/Rh screening should not be used as a triage mechanism. Future investigations can focus on the creation of a global COVID-19 database to account for population-based differences in blood types and testing protocols. In addition, further studies are necessary to understand the molecular mechanisms by which blood types might engender susceptibility to SARS-CoV-2 infection, and ultimately, develop countermeasures to viral infection and illness.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8286549/
Why is the outcome so different from the others I have highlighted?