In spite of all the troubling bigotry and narcissism from Trump, I still think that one of his major issues is a lack of experience in politics.
I don't think it's lack of experience as much as lack of Curiosity, and lack of Appreciation for government.
I mean, most of us on this forum aren't elected officials, but almost all of us (sadly) know more than Trump does and would behave better than Trump has been behaving. It's because we have a Curiosity that has led us to research these things about both policies and process, and for many of us there's some kind of Appreciation for the process of government. Whereas Trump doesn't think government works so he isn't filling posts and isn't following procedures, likes putting the system in chaos, isn't naturally curious and just wants to get his way, etc.