That's a somewhat unwarranted statement. People - are people. It is better to try to understand exactly what that means. By rationalizing that definition, one does what many people do not - discipline their responses instead of reacting.
I have often noted that there are two extremes to people, those who blindly react to their environment and those who exercise intellectual and spiritual discipline to rationalize disciplined responses to their environment.
And certainly, there are more people at the reactant end of the scale, then at the disciplined response end. But they are your fellow humankind, citizens and neighbors. It is easy to take exceptions to behaviors and differences in other people, but it is better to do a little bit of work to rationalize and understand them, tolerate and perhaps, even provide some positive guidance.
The reactant personalities are collective. They share their common grounds as recognition for inclusion in community. And that is good. Yet they also draw unnecessary lines between themselves where they see variance in those common grounds.
The disciplined thinker is by nature a variant of the common ground, sometimes avoiding the crowds and community to find peace and contentment where the crowd and community may promote discontent and even hostility. Rational explanations are not favored among the reactant crowd. It is perhaps taken as an effort to manipulate and control - and nobody favors that. I learned long ago, that to try and help people is therefore a difficult task which takes an extraordinary talent.
Such are people. And you and I and they, must respect each other