At the end of the day, the presidency is the only position that is beyond the reproach of anyone behind the scenes that may be using their powers to pull strings. If he has ever been coerced by hidden powers, he alone could unveil them and be believed by all the non-believers. Alternatively, he could choose to promise exercise his pardon rights for people who want to expose wrongdoing but are afraid. He had the power to protect people from jail. That's the power to allow people to expose wrongdoing without fear of retaliation (unless we've gone so far down the rabbit hole that someone can make the whistleblower just disappear.)