Because even doctors are people and some people are stupid / frauds. They say they are treating people, but provide no statistical data or proof that they have done trials explaining their methods? Why is that? I've given the medicine to 20 people, and they all died. Don't believe me? Well, I put it on Twitter, so it must be true.
It's not how medicine works. It's not opinion, it's not politics, it's science. If they can prove that it works, back it up with data, like the people that say it is potentially harmful do. I'm talking about cocktails of seperately harmless drugs that, when taken together, are harmful or fatal. Which is a counter point to your claim that the drug must be safe since some people are treated with it. You don't take drugs in a vacuum (I think, I'm not sure what happens in the ISS), someone's condition and other medication plays a very big part in what happens. That's why, even when using something normally harmless is researched exstensively when being used with different types of medicine. This research takes time, of course, and some people will die, but medicine has developed this far by adhering to strict scientific methods.
Morons like Trump try to discredit science when results don't suit them and people, being the stupid / frauds they are, fall for it. It's like he's trying to prove Darwin wrong by making humankind devolve.
I have to say, if I were a pro Trump person I would definitely post on the caf, the amount of response you get is amazing