> economic stagnancy
It's not some god given rule that cities HAVE to keep growing ad infinitum, especially ones that have limited land. Most San Franciscans are happy with the size of the city as it is.
> transportation nightmares
I'm not sure what you are referring to here. MUNI is very abundant and isn't too expensive (compared to NYC it's really cheap). There is generally plenty of parking outside of downtown.
> destroying traditional neighborhood demographics
Lol. The Chinese are doing just fine, but I guess you're referring to the former ghettos (Lower Filmore, Hunter's Point, the TL, etc.) that had huge drug problems and violence (It's still there, but siginificantly reduced) Yes, gentrification is unfortunate - but building high rises everywhere would ruin the "culture" much faster (though I would argue the Tenderloin doesn't have much culture to lose) and wouldn't solve the poverty among "traditional neighborhood demographics". What needs to be done, is a lot more needs to be spent on schools and city college and less on low income housing (where people are locked into poverty).
> very fundamental quality of life
That's just a vapid hyperbole. Not building high rises is preserving the quality of life SF is known for. The NewYorkification of SF (started by the Gavin Newsome) is what will ruin the quality of life.
In my experience the people that whine and moan about there not being enough housing in SF are people that don't live there. I think what they're thinking is if there were more teeny tiny apartments then they could afford to live there. While that may be true, then SF wouldn't be SF anymore - and it would only be a short term fix as SF would become just as crowded and expensive as Manhattan.