Politicians & political parties have historically low approval ratings - what does this tell you?
Yet they all keep winning. The two-party system persists. Why? Because the American people don't elect politicians... corporations do.
The problem started in 2000 with the appointment of George Walker Bush by the SCOTUS. But the Citizens United ruling made the situation much worse. Corporations now have grossly disproportionate power. They effectively choose our politicians, and they always chose pro-business puppets who will do as they're told.
It's become so bad that even independently wealthy candidates can't win. You have to be endorsed by the powers-that-be. You have to be indebted to corporate America. You can't make it on your own, that's too risky. You have to be beholden to the 1%, otherwise you're a wildcard.
It's not as if Americans are ignorant to the problem... it's that Americans are powerless to change it.