The democrats have been trying to raise minimum wage for idk 15 years now, they just haven't been given a functional enough majority to make it happen at the national level, though they have absolutely done so at the state level. I think your complaint might be misdirected, and could better apply to the fundamental structure of our bicameral legislature, and especially at the filibuster rule that is getting increasingly unpopular with senators themselves. When the filibuster is gone sometime in the next 6 years I expect, you will see a noticeably more functional senate.