This is why critical thinking is such an essential skill. So many people out there are convinced about things with bullshit arguments, just because the person talking is charismatic/confident or popular and influential.
Note: Critically thinking doesn't mean denying everyone and everything and holding controversial beliefs in order to feel smarter than others, it often starts with admitting your very own mistakes first. Just like with other's arguments you should be applying the same checks to your own thinking and notice your own fallacies to correct them.