If the conspiracy theory of both corrupt mass media and the corrupt medical-industrial complex conspired to bury potential earth shattering and life saving treatment protocols for mutual self serving financial gain, then practically every doctor and hospital on earth was in on the scam and not a single individual in the medical community spilled the beans.
Conspiracy theory! is not an argument. We do our best to design public institutions that apply policies and make decisions that are both fair and accurate. A good part of that design has to do with disincentivizing the abundance of self-serving or erroneous views. Even the best institutions imperfectly succeed at that goal. Thousands of intended petty corruptions can add up to an unintended grand corruption. If steel companies share common interests, each can seek and policymakers can provide, even if the companies never communicate with one another. See GIlens and Page on who rules America and Winters and Page on oligarchy in the U.S. These are mainstream political scientists at top institutions, not fringe bloggers.
Additionally, as OP here, almost everyone outside their narrow range of expertise evaluates new information not by personal investigation but on the basis of their estimate of the credibility of the messengers. That is how epistemic bubbles can emerge - and propagandists know how take advantage of our reliance on social proof.
In the U.S., useless Remdesivir is approved; useful aspirin or Vitamin D are ignored. There is no global conspiracy: breakthroughs are coming from outside the US CDC-FDA-NIH-BigPharma bubble.
I don’t want to out myself so I’ll be a bit vague – I am familiar with public policy analysis, social science, causal identification, research design, philosophy of science.
Multisite, blinded, random controlled trials do provide very good evidence that something is efficacious and safe. They do NOT necessarily show that something doesn’t work – accidentally or deliberately they can, for example, be underdosed or dangerously overdosed, omit a necessary cotreatment, be administered at the wrong phase of the disease, and so on.
There is an influential movement to demand RCTs for public policy decisions. It is salutary in focusing our attention on fallacies of causal inference. Like their counterparts in public health, however, many of these advocates can be zealous, dogmatic, and ultimately unscientific. To borrow from legal terminology, their method demands that decisions be based on a standard of beyond a reasonable doubt. But, in public policy, as in public health, failure to act can do harm, can kill. Most such decisions (especially in an emergency pandemic that kills and disables) should be based on the standard of the preponderance of the evidence (or where equities demand, clear and convincing evidence), based on the entirety of established principles and available evidence, appropriately weighted for quality. The U.S. Constitution, and the victory of the Allies in World War Two, were not based on evidence from public-policy RCTs.
During this pandemic, U.S. public health has been exposed in a gross albeit unintended hypocrisy. If multisite, blinded, random controlled trials are the standard for public decision, then all of the recommended or required Covid-19 public-health social measures (which I personally accept) are not justified and can’t be imposed. Handwashing, masks, social distancing, lockdowns, testing and tracing, and the lot. These measures have NOT been shown efficacious and safe with highest quality RCT evidence for Covid-19. They can satisfy common sense, they can be based on reasonable extrapolation from established principles, they can have good evidence – but not evidence beyond a reasonable doubt based on multiple well-designed RCTs. Even if strongly supported in general, they have not been shown to be efficacious and safe for the Coviud-19 disease, for the disease in the United States, for all age groups, races, genders, and so on.
Safety is important. Repurposing of old treatments should preferably focus on items that are well-established as relatively safe, like aspirin, Vitamin D, Ivermectin. If their efficacy is probable rather than nearly certain, it is likely that some good and little harm has been done. Handwashing and masks are relatively safe, and are supported by good but not perfect evidence. Universal lockdown does immense harm, quite plausibly more harm than good in terms of lost life years (we need and practically will never get multiple RCTs – for perfect knowledge we can’t compare Sweden, Norway, and U.K. because treatment is not randomized – there are too many potential confounds).
Can we compare the benefits and costs of aggressive lockdown to those of a regime of prophylaxis and early treatment with cheap and safe repurposed treatments? According to U.S. public health, only good evidence is required for even a coercive social measure, but perfect evidence is required for a direct medical measure. We cannot risk any harm by allowing a pharmaceutical measure, but can freely risk harm by forbidding a pharmaceutical measure, and can freely risk harm by imposing draconian social measures.
But, but, but tens of thousands of highly educated and well-intentioned people in respectable institutions do endorse these absurdly inconsistent policy positions! Not an argument, That’s the bandwagon fallacy. Thousands of obstetricians firmly believed that handwashing was not required during delivery and fiercely persecuted Semmelweiss who first advocated for it.
Sorry for going too long, got carried away, I’m working this out in my own mind.