That's a common sentiment, and I think there are a few points against it:

1. SF could double it's current housing density tomorrow and still have less than half of manhatten's density. That's not a serious concern.

2. Even if it were, we're faced with a tough choice: preserve SF's low-density housing, or preserve it's people. Which is better: a city with 20% taller buildings, or a city where the only the rich can afford to live, secure in their $10m victorians and $5k/mo NEMA towers?

3. Many would argue that SF's uniqueness is its population, its freespirited attitude, and its rich history of art and culture. The buildings themselves are only a small part of that. Losing them would be a bummer, but far worse than losing the real soul of the city.

I'm not disagreeing with anything that you said. I'm just lamenting the fact that SF will look just like every other skyscraper style skyline. You won't even know where you are

<SF could double it's current housing density tomorrow and still have less than half of manhatten's density. That's not a serious concern.>

Count how many bridges and tubes connect Manhattan to the mainland vs. how many bridges and freeways connect SF to the rest of the world, and revisit that concept again.

You could cut housing prices in half by building 111,000 new units. You could do that by converting 6% of the city's single-family homes into six-story apartment buildings, leaving the other 94% untouched, and not building a single structure taller than that.

I'm not arguing against development. I'm just saying that the iconic look and feel of SF will be lost. Maybe that's inevitable, but it saddens many people

Tokyo and Mexico City have very, very few buildings over five stories and still have double the density of SF. Paris and Barcelona have almost none over seven stories and have four times the density of SF.

So it doesn't have to be high rises and skyscrapers. SF can look like SF and build enough to make living affordable.

Of course, the real problem is the peninsula cities that insist on densities much lower than one third of SF. 80% of buildable land on the peninsula is tied up there being wasted.

When is the point of peak beauty? 1900? 1850?

Also, Hong Kong is a rather beautiful city.

Singapore looks like a giant shopping mall. It's nice in its own right, sure but I don't think I want every city in the world to look like it

don't worry. they won't. take LA for instance. most parts of it look like a giant traffic jam. looking like a nice shopping mall would be a welcome upgrade. LA will never look as nice as Singapore. Singapore has a huge amount of surplus investment cash. LA's budget is constantly at a breaking point.