My brother, who has a Ph.D. in pure mathematics, says that all a doctorate means is that you’ve learned to talk a lot.

I don’t and never will have one, so this is the only relevant information I have.

Slight correction based on my experience and because even without a PhD, people regularly put in the time to become subject matter experts:

Someone with a PhD isn’t inherently more intelligent than other humans. They are able to put up with the institution abuse and bullshit required to be given a title that designates them as a subject matter expert in a field.

No shade to PhDs, I feel your pain.