Why are there so many remarkably awful members of Congress, particularly on the GOP side? Part of the answer has to be that Congress is no longer an equal partner in government. If the legislature no longer plays much of a role in making policy, and does not legislate, then what is the point in being a hard-working team player? Real power lies in the manipulation of social media and the gathering of attention, not the production of useful legislation.
Killing the filibuster would change these incentives. If the voters had reason to judge the effectiveness of a legislator based on his actual production instead of the violence of his rhetoric, we might get a better class of legislator.