Earlier quoted context omitted.
It's an excellent point. Learning is not the same as science, and we need randomized trials to actually be sure of anything. Unfortunately, in the middle of a pandemic, that's not going to happen with enough speed to prevent a lot of people dying. The perfect can be the enemy of the good enough. We don't have to guess or learn about the mass of an electron; that's been well-established through great lab work. But not…
> Unfortunately, in the middle of a pandemic, that's not going to happen with enough speed to prevent a lot of people dying. How are you sure that this method is not worse than the ventilator method and will kill even more people during the pandemic? How many death did they get with this method? How many death would they had got with the ventilator method?
It's not that your questions are bad, it's that in practice medical professionals have to operate without answers to them. Doing so involves communication with peers about their own observations of what may work better/worse, such as in this article. Double-blind randomized trials are not the only source of actionable information: Case studies also form a significant pillar of knowledge, especially pending results from more systematic studies.
[0] https://link.springer.com/chapter/10.1007/978-1-4757-2068-6_...