Congress neutered itself, largely because it has been politically less risky to let the Executive branch do whatever they want, then either cheer it on or rage against it depending on party and what drives donations so congress members can get reelected.
I agree that it's fundamentally broken but I've been around to see it work and watch it fail.
The executive branch obviously is going to wield as much power as it can, but only one party is actually advocating for the executive as king.
So yes, both parties are the same when it comes to the corruption of the party leadership, but there are distinctly different platforms and ideals espoused -- and that difference matters.
The system is fundamentally broken.