The aesthetic of suburbia is exclusion. That's what makes it less valid. It's reaping the benefits of access to the city while minimizing the number of others who can do the same. There's nothing wrong with liking solitude, but there's everything wrong with insisting that we preserve your solitude on the most central/best connected land, no matter the cost to everyone else.

SF's unoccupied blocks are pretty much built out by now. Everywhere with preexisting residents is the same: I came here because I liked the neighborhood as it is, it can never be allowed to change.

Cities aren't plopped down out of the sky fully formed. They're living organisms, built by expanding iteratively and incrementally. The city that's already been built is full. For more people to live in city, we need to make more of it. Aside from a fire or earthquake providing a clean slate, intensifying the suburbs with the best access is essentially the only way that happens.

This would be fine, except that economic growth is increasingly accruing to a handful of cities whose zoning is a big Keep Out sign.