That might be valid if we were still dealing with the politics of yesteryear where the assumption was that politicians would compromise and vote for their constituents best interests and not simply their political party no matter what.
The fatal flaw of the founding fathers was that they assumed men would continue to have a conscience and morality. They felt that perhaps one or two bad apples might find their way into political positions, but couldn’t fathom an entire party of them.
When you have a party of traitors working to undermine democracy, you no longer are able to function as intended.