Practically there is no way to hold a doctor accountable. There's various laws to limit liability and in most courts in the US you'll need another doctor to testify against your doctor. As the number of doctors is low they tend to know each other at least in passing, and it's hard to actually enforce professional standards.
What matters the most are practicing doctors, not doctors involved in research. I forget what the numbers are, but there are still more GPs and specialist than there are researching practitioners.
If you venture far outside a big city the quality of healthcare experiences a precipitous drop. It's terrifying. Even within a big city like New York, we found out that the ER/ICU professionals were killing people with ventilators! Why didn't they just supply oxygen instead, like they seem to be doing now?
Hyperbolic sycophantry like the above only exaserbates the ego and credentialism problems which already plague the medical profession. Respect is earned.
Doctors are, and should be, some of the most elite minds and highly respected scientists/caregivers. Like any group, they have inter-group controversy and debate, but let's not use that to pile onto the anti-science, anti-vax, anti-medical chorus which is gaining steam on the internet. Some doctors get things wrong: most doctors, however, enact evidence-based practices which have been vetted by statisticians, chemists, and physicists who help innovate and inform medical decision-making.
As high-minded as our concerns about doctors being incorrect might be, let's keep a wide view here and not tear down a vast-majority noble and expert profession. Let's have a nuanced discussion where we admit doctors are both experts, highly select, but also people with flaws too.