"He had altruistic motives and held steadfast to principles that he promised his readership."

I think that you fundamentally misunderstand the film. Charles Foster Kane did everything the way that he wanted to do it. Listen to Jedediah Leland letting him know: "You don't care about anything except you. You just want to persuade people that you love 'em so much that they ought to love you back. Only you want love on your own terms. Something to be played your way, according to your rules." Jedediah and Susan were the only characters that would tell Kane what a monster he was, but the person that kept him from being governor was a crooked politician.

The film shows that people will not be altruistic, given the wealth. Kane's newspaper goaded the country into a war with Spain to increase circulation, just like publisher William Randoph Hearst did in real life. That's appalling, and to make it worse they had a party about it. The movie was based on Hearst's life, and he tried to block the film from being shown. If there is a lesson in the movie, it's that society essentially doesn't change, and neither do people. Rich people controlled the mass media then, and they do it now. Jeff Bezos owns the Washington Post.