There are people who ask tough questions, who (at least theoretically) are willing to change their mind if the evidence points the other way, who don’t pretend to know all the answers, who can see both sides of the debate when warranted. I like those people. We need more of those people.
Then, there are those people who are stubborn, who cling to their beliefs no matter what the evidence says otherwise, who think that the person who’s right is the person who’s the loudest. We can do without them.