It's true, but also, possibly less important than the "first in, last out" epistemology that most people run on. We tend to hold whatever opinion we hear first, unless someone produces a very strong argument against it, and the longer you hold that idea before anyone challenges it, the less likely you are to change it regardless of the evidence.

Loud mouth pundits tend to be most people's first-pass at any idea, so whether it's true or not, they get to decide what you're going to think for the rest of your life