Not all that long ago, the clown car primaries resulted in a crush of candidates trying to out-left each other by adapting new insane lefty proposal.
The crash may have come when Bernie Sanders decided to endorse the Boston Bomber voting from prison at the behest of the ACLU. The proposal polled badly and came to embody the kind of terrible baggage that no candidate would want to carry into the general election.
Biden strode into the primaries and dismissed lefties. Buttigieg made it to third place by trying to sound like a moderate. Neither Biden nor Buttigieg are moderates. But they consciously made the decision to shift the tone toward the center, instead of pandering all the time to the extremes.
Pre-Biden, the primaries had been about beating Sanders by co-opting his radicalism. Now they're starting to tilt toward beating Biden.
The radical candidates, Sanders and Warren have consolidated much of their support. But Democrats have largely embraced Biden. And as a result we're seeing fewer crazy proposals coming out of the major candidates not named Sanders or Warren.
Meanwhile the rest of the clown car, like Cory Booker, are hopelessly clamoring for attention with radical proposals. But the only thing that does is demonstrate their irrelevance.