Apologies if this has already been addressed, but here's my small effort to combat dangerous misinformation.
TLDR: the linked article in the original post is misleading, to say the least. You should think of it as the science journal equivalent of an opinion/editorial piece in a newspaper.
1) This is not a "study," it's what most journals would term a review article. The author did not do any original research, he's just giving his interpretation/opinion of a bunch of other studies. He's also not an expert on this topic, except for possibly the effects of wearing a mask while exercising - his degree is in clinical exercise physiology.
2) To be generous, I'll call his conclusions "a big stretch." To be more specific, the articles he cites as evidence for his claims fall under three categories: articles that have been debunked/outweighed by other results, textbooks/manuals with no specific reference to a particular section (i.e. useless), and articles that say the complete opposite of what this author says they do. For example, this questionable claim:
"Due to the difference in sizes between SARS-CoV-2 diameter and facemasks thread diameter (the virus is 1000 times smaller), SARS-CoV-2 can easily pass through any facemask"
cites
https://pubmed.ncbi.nlm.nih.gov/32329337/ as evidence. The results of that study in fact indicate "combinations of various commonly available fabrics used in cloth masks can potentially provide significant protection against the transmission of aerosol particles," with surgical masks being more effective than common cloth masks for smaller particle sizes (although both still reduced transmission).
3) Any article from the
Medical Hypotheses journal that this was published in should not be considered settled science. The journal's goal is to, in short, publish opinion articles that "foster the diversity and debate upon which the scientific process thrives," not to present research. You can read the full statement here:
https://www.sciencedirect.com/journa...aims-and-scope.