No, but many people function (through choice or otherwise) in areas where the things at which they are good are not so apparent. I mean, yes, some people are idiots, but most aren't.
If the guy from my local garage were to try to do my job, he would mostly likely look like an idiot; if I were to try to do his, I would definitely look like an idiot. Same across all skills/professions/walks of life.
Then there are, of course, the people who pretend the Daily Mail is a real newspaper. People who prefix their statement with 'I know it was in the Daily Mail, but...' and then repeat the thing they read in the Daily Mail as though it were true, even though they've prefixed the statement with an acknowledgement that it most likely isn't!