I thought so too. But we didn't go through this soul searching. Even today, left-wing writers do not ask why the system did not filter out Mr. Trump in 2016.
It is not a far stretch that there are internal forces in the D Party that would prefer the D's to run the show than give the reins back to the Republicans. Call it a preemptive strike--and many Americans would prefer this outcome. The oligarchy scenario can swing either way.