Manchin is a problem, as is Biden's neoliberal tendencies toward market solutions to all economic issues. However, the turd in the punchbowl of our government is, and has been for some time, Mitch McConnell and the bat-sh*t crazy Republicans that vote for such a conniving morally depraved individual that does nothing for them and is proud of it.
The trend among conservatives to mistrust their "elected" government to the extent of being constantly at the edge of a bloody revolution will have to be dealt with eventually, by extreme force. Their fantasy of "small gubmint" became moot after WWII and yet they are gathering together, even now after the Jan 16th debacle to plan the overthrow of the nation and replacement with some mix of 18th-century economics and Mad Max dystopian wet dreams.
The extent to which this has crippled the only entity that can regulate and tax business and its wealthy investment class owners is the only reason the Republican party has any financial support from the oligarchy. However, that support has proven successful beyond anyone's wildest dreams in forming a fascist society with the full and undying fealty of half the population.
One can almost (but not quite) understand why the Democratic party and its leadership doesn't want to fight the current while it is offered a seat at the grand table among the elite. I'd likely be reluctant to fight for the best interests of a population of cousin humping rednecks after being labeled "sushulist commie" by those who can vote but can't add to anything above 21 without taking off their shoes and unzipping their fly.