Using your logic, if any health supplement company made a claim saying their supplements say Vitamin C and Zinc is good for COVID-19 without any conclusive evidence is ethical? Sorry, I just can't agee with it. My point is pharma/ health supplement companies should only make a claim AFTER they have conduct clinical trials not before. For instance, in this case, MGC can claim they have found a potential treatment of COVID AFTER they have conducted some studies which show promising result, not beforehand. At the end of the day, Artemisinin is only found to be effective as an anti-malaria so it is inappropriate to assume it will work for other diseases such as COVID-19.
I have a look on all the link you have given. They are all isolated studies and is considered as "weak" evidence in the eye of health professionals. You should use more creditable source such as NPS review or Cochrane library such contains mega-analysis and from a more credible source.
Google search is definitely a bad idea and a lot of links you provided are biased as the information are from manufacturers. Ask your doctor or pharmacists who are working in medical field and ask for their opinion if you want.
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