And who do you go to when you have a medical issue? Surely not a doctor/hospital, since you're so anti-credentialism.

Pretty sure it works out well more often than not. In a Bayesian sense, expertise signifiers are more useful for updating priors than a lack thereof.

Most people invoking "appeal to authority" are not uncredentialed autodidacts who have secretly figured out something mainstream science has missed, but vaccine skeptics reading Facebook, or HN commenters who think they can figure out whole other disciplines from first principles.

It’s “fallacious appeal to authority”. This means don’t talk to your yoga teacher about vaccines. Authority exists.