This was a Chinese study, so like with any information coming from China be suspicious of its accuracy:
People with type A blood are more likely to catch coronavirus while those with type O seem more resistant, a preliminary study of about 2,000 patients in China showed.
Korea Times
A team of Chinese researchers, led by Wang Xinghuan from the Centre for Evidence-Based and Translational Medicine at Zhongnan Hospital of Wuhan University, conducted the study.
They took blood group patterns of patients in Wuhan and Shenzhen and compared them to local healthy populations. They found that blood type A patients showed a higher rate of infection and tended to develop more severe symptoms.
In the general population, type O blood (34 percent) is more common than type A (32 percent). But in the infected, this was reversed, with type O people at 25 percent and type A at 41 percent. People with type O blood made up 25 percent of deaths in the research. Normally, people with type O blood account for 32 percent Wuhan’s population.
You can read more at the link.