This turnaround is because the political class/establishment got scared from both the Virginia (and somewhat New Jersey race), and in Seatle where people elected a republican DA. https://www.washingtonpost.com/nation/2021/11/06/seattle-ele...
The 'progressives' and their insane left wing policies, are causing a major regress of quality of life of everyone in the city, and the rest of the country is paying attention. This is the rest of the political establishment trying to save their skin, and jumping from the sinking ship and trying to reverse course.
Also, both CA (LA and SA), and Seattle and Chicago are what happens when a region becomes a one party state. There is no more competition and the establishment gets entrenched to the point that it hard to dislodge, and they can enact all kind of crazy policies, that don't benefit their constituents.
The same thing, but opposite ideology (right wing), is in Hungary, Poland, and Turkey. (Orban and Erdogan are the opposite side of the same coin. Super entrenched majority, that is hard to kick out, and steer the place into regress, corruption or mismanagement).
Moral of the story: Don't vote blindly for one party. If the current elected leaders are not making your life better, vote them out.