Agreed. And in my opinion, a big part of the rot was that Congress became progressively more dysfunctional. (When was the last time they passed an annual budget? That is the most basic job of Congress, and they haven't been able to do it for years.)
I'm not going to argue the "progressively dysfunctional". The Hastert Rule has a lot to do with that. Individual members can't cut deals for votes any more. But it looks like there have been appropriations bills every year.
Don't take this as disagreement with your basic assertion. Failing to declare war since 1941, failing to impeach and convict Clinton, failure to impeach and convict Trump at least once, the House checks and balances Dem presidents, and aids and abets Republicans. It's a gerontocractic farce.