I've visited and I wouldn't say that is true. There is all kinds of seedy. There are white/skinny seedy people walking rats, kinda freaky. But taking the downtown bus gave equal race representation when someone started a fight with me over there bag's right to occupy my seat. The Asian gangs robbing/hitting people on the bart I was on showed a different side of seedy. The uniquely San Fran treat was someone asking my opinion on my beat poetry they wrote around race struggles. After commenting positively (just to be nice) said Poet offered to sell and when refused when on racial rant and become very aggressive.

It's a diverse place of seed and rich. It's a very future feeling place. The experience made me think this is a slice of what the future will look like. It's kinda has this dystopian gothic novel feel. The mini subways (barts) are automated and cool and look like they are in the future but look like they are falling apart too. You get this weird post apocalyptic feeling of a future that has come and gone but hasn't reached you yet

I personally don't hold that opinion, but this could still be construed as racist.