Hey guys, sorry to bother you today, but where is the line between political correctness being a barrier, and someone just wanting to say stupid stuff?

For example, someone may say something ridiculous (to me, it is) like “We should be checking muslim people more at airports instead of being politically correct and treating everyone equally.”

Sometimes it seems people use the “we have to be politically correct” excuse because they don’t want to be chastised for saying something uninformed or ignorant.

Is there something that political correctness actually acts as a barrier to?