You’ve glossed over “failed policies that nobody has reversed for decades”. The boomers have augmented and promoted these failed policies from their inception.
It makes them feel good to have nice thoughts, results be damned. The boomers have coasted on the affluence won by the greatest generation, they are presiding over the decline.
There are many people who could have reversed these policies, but they were put into place by a generation conditioned by FDR and his massive federal takeover, and I think that made it unthinkable to do a wholesale reversal. Also, once the money starts flowing, everybody buys into it. Look at the black race pimps, look at all the “agencies” and NGOs that make money on the poverty industry.
Heck, Nixon (elected by boomers as a conservative) even extended the LBJ policies.