The source being cited for this topic/post is a secondary source (technically tertiary since its source is a meta-analysis of several individual studies, which would hence be the original sources). If one truly wants to understand the research and create their own complete, unbiased conclusion of its findings, they should read the original article. I will link it here:
https://www.cochranelibrary.com/cdsr...6207.pub6/full
.................................................. .......... etc., etc., etc.
It takes LOTS of time and effort in the academic field for anything to get published (i.e., years and sometimes decades), and the pandemic event itself is only a few years old. It's important for mankind to learn quickly in order to grow and improve on how we approach things in the future, but research takes time and we should be patient until said research is more developed before making final conclusions.