The Democrats enable this. They know exactly what they are doing, and have the same corporate sponsors as the Republicans. They spent literally billions of dollars to railroad Sanders’ agenda, but let Manchin and Sinema run amok. They do that because Manchin and Sinema are the levers by which they can either decide to make something policy or use as an excuse why they couldn’t adopt some policy, since somehow the two parties are always split 50/50 in some magical way that coincidentally benefits their corporate rulers.
The Democrats work with the Republicans to enact the corporatist agenda.