Simple…
The young people of America think that the Democrats are wholly owned subsidiaries of corporate America and old fogies. They see NO reason to get off their asses to vote for them and, frankly, the only good reason is that the other party is now fascist. This leaves Biden no choice. He must show that there are actual benefits for Democrats being in power and that means he must use the money earmarked for BBB and cancel student loan debt.
As far as Manchin goes, Democrats need to condemn him in the strongest terms. Who gives a shit what he does now? Go to the Republicans. That’s a good way to get wiped out in a primary. Be an obstructionist asshole. He’s already that. Democrats need to treat him like he is the enemy because he is.
Edit: Internet filters don’t like fuck, so I changed it to f*ck in the title at DK’s request. That said, fuck Manchin.