The tipping point of concern for the anti-gentrification crowd isn't "is it profitable to upzone", it's "will upzoning make things cheaper" and those are VERY different questions.
But just going on the numbers for the former question, the "expensive" city centers in the US generally start with Manhattan, Brooklyn, SF, and whatever you'd call "center" of LA. And they don't seem that far behind a lot of the rest of the developed world...
Manhattan is >70k/sqmile.
Brooklyn is 37k/sqmile.
SF is ~19k/sqmile.
LA is 8k/sqmile.
So what are the "bog-standard suburban towns" you think they're comparable to?
I can't think of many, and my searching isn't turning many up. Milan appears to be 20k/sqmile while Rome is 6k/sqmile. And those aren't "bog standard suburbs" like a Marietta, Georgia; those are central cities! Let's go bigger and even more central - London is 15k/sqmile, Paris is 53k/sqmile. Tokyo is ~17k (and larger, more like a double-size LA, there), but not overall denser than the US's expensive city centers. Manchester, in the UK, is 5450/sqmile. Stuttgart is 7,800/sqmile.
Manchester is apparently comparable to San Jose! So again, seems like the way to fix is it to focus on the places further down the list, like an Austin, TX, at 3k/sqmile.
But just going on the numbers for the former question, the "expensive" city centers in the US generally start with Manhattan, Brooklyn, SF, and whatever you'd call "center" of LA. And they don't seem that far behind a lot of the rest of the developed world...
Manhattan is >70k/sqmile.
Brooklyn is 37k/sqmile.
SF is ~19k/sqmile.
LA is 8k/sqmile.
So what are the "bog-standard suburban towns" you think they're comparable to?
I can't think of many, and my searching isn't turning many up. Milan appears to be 20k/sqmile while Rome is 6k/sqmile. And those aren't "bog standard suburbs" like a Marietta, Georgia; those are central cities! Let's go bigger and even more central - London is 15k/sqmile, Paris is 53k/sqmile. Tokyo is ~17k (and larger, more like a double-size LA, there), but not overall denser than the US's expensive city centers. Manchester, in the UK, is 5450/sqmile. Stuttgart is 7,800/sqmile.
Manchester is apparently comparable to San Jose! So again, seems like the way to fix is it to focus on the places further down the list, like an Austin, TX, at 3k/sqmile.