Why would the number of stupid people who believe something anticorrelate with the number of smart people who believe it? Most stupid people and most smart people believe the sky is blue. A shift in the fraction of stupid people who do X can take place without any corresponding shift in the fraction of smart people who do X one way or another. Some smart people actively prefer not to affiliate themselves with stupid people and will try to believe something different, but they are committing the error of the OP and should not be listened to anyway.
Why would the number of stupid people who believe something anticorrelate with the number of smart people who believe it? Most stupid people and most smart people believe the sky is blue. A shift in the fraction of stupid people who do X can take place without any corresponding shift in the fraction of smart people who do X one way or another. Some smart people actively prefer not to affiliate themselves with stupid people and will try to believe something different, but they are committing the error of the OP and should not be listened to anyway.