We don't want bad laws. Preventing them is good. Requiring 60% to pass a law is one of the best rules we have.
The only problem is that we do want to repeal bad laws, and we need to pass a budget. And the filibuster prevents us from doing those things. We should change the rules so we need 60% to pass a law, but only 50% + 1 to repeal a law or pass a budget.