After WWII, SF was somewhat sophisticated and eclectic.
By the late 60s, SF was dropping as depicted in the Dirty Harry Movies, showing the dichotomy between the left and conservative crowd or just simple normalcy.
By the late 80s, SF was just recognized for having some wealthy portions, and generally no sophistication whatsoever. Homosexuality was normalized. Military was being run out of the Bay Area.
By the 2000s, indigents and illegal aliens were promoted and declared as a sanctuary city even when they murdered people.
2020s don’t indicate any sign or turnaround other than further degeneracy and collapse.
In many ways, it was WW2 that sealed SF’s doom.
SF was the primary intake center for draftees in the western divide of the country (I don’t recall if it was everything west of the Mississippi or the Rockies?)
Anyway, many of the dysfunctional and depraved that failed their draft screening generally decided to settle in SF rather than return home and face the shame of friends and family.
So, basically, the weak, psychologically/mentally unfit, communist and homosexuals of a large portion of our country was condensed into San Francisco.