I think you underestimate someone as successful as Trump in a leadership position. Most people do politics as a career, they have to suck up to 'x' and 'y' to get ahead, which means obligations later on. Eventually, when you get to the top, you have tons of people with dirt on you that you have to appease.
Sponsors also become a major issue, since you have to do as they say in order to stay funded.

Then you have Trump. Doesn't owe anybody anything, doesn't give a flying fuck about his political career because he's already massively successful. He can do what he wants, how he wants it (within the confines of the system of course) without an image to uphold, or a career to take into consideration while doing it.

I'm a huge fan of making politics a non-paying job*, so only those without self-interest can take part. Corruption would still be somewhat of an issue, but you'd get a lot of people that want that power to do something meaningful, rather than be an empty suit collecting a paycheck.

*(In Hungary, being a member of the Assembly is a job, with pay. Not sure about other places, such as the US. )