To the ignorant, there is precious little to discern between the ravings of a lunatic, and the soliloquy of a genius (seeing as how they understand neither). Add to that, the fear that the average person has, that they might end up looking even more foolish than they already are, and you get the perfect opportunity to have a lunatic passed off as a genius.
Enter Gary Busey.
Somewhere along the line, "somebody" (and likely nobody knows who that might have been) ended up referring to Gary as some sort of genius. You can't un-ring a bell, and once "somebody" states that Gary is a genius, every other moron that doesn't want the fact that they're ignorant made public, has to agree. Now, we have a lunatic going on publicly televised rants. Then, we have a moron like Donald Trump, who doesn't want to appear ignorant, making those lunacies out to be somehow intelligent.
And now, there you have it. The modern day remake of The Emperor's New Clothes. If you'll recall, the Emperor walked around naked, thinking that he had new clothes that only wise people can see, until a child cries out that he isn't wearing anything at all. Gary's not saying anything at all, but in people's efforts to seem smarter than they are, they all pretend that they are hearing words of wisdom.
Shine on, you crazy diamond!