In the long fight to keep California’s wealthy, homogeneous, exclusive suburbs just the way they are, Palo Alto and Beverly Hills have an ally they might not have expected: San Francisco.

The city’s Board of Supervisors — thanks to its purportedly progressive faction, no less — is poised to reiterate its reactionary resistance to legislation that would legalize higher-density residential development near mass transit amid a crushing housing shortage.

Despite San Francisco’s obvious differences from the suburbs that surround it and other California cities, the supervisors’ latest act of housing-crisis denial isn’t particularly surprising. Many of the cities’ neighborhoods are like Palo Alto and Beverly Hills insofar as they outlaw apartments and remain resolutely out of reach to most Californians. The supervisors, progressive pretensions aside, are representing this reality — and doing their best to perpetuate it.

While the supervisors’ position hasn’t changed, state Sen. Scott Wiener’s SB50, the bill they’re opposing, has. Since it was killed in committee last year, as SB827, the San Francisco Democrat has revised it by moderating allowed building heights, increasing affordable-housing requirements, adding protections for rental housing and gentrification-prone neighborhoods, and extending it to high-employment, housing-scarce areas even if they aren’t near train or bus lines.

The broadened support for the bill reflects these substantial concessions. Trade unions and environmental groups have joined affordable-housing advocates and developers in supporting the legislation. So have the mayors of the Bay Area’s three biggest cities, San Francisco’s London Breed, Oakland’s Libby Schaaf and San Jose’s Sam Liccardo. And unlike its predecessor, SB50 passed its first committee this week.

The opposition still includes tenant groups that fear more gentrification of neighborhoods like the Mission. But apartment development has been driven into those areas because it’s excluded from richer neighborhoods and suburbs.

It’s those exclusive neighborhoods that are most implacable in their opposition lest they be forced to open their borders to anything more affordable than a single-family home. An analysis by UC Berkeley’s Terner Center for Housing Innovation and the Urban Displacement Project, comparing hypothetical post-SB50 developments in Oakland’s Fruitvale neighborhood and Menlo Park, found the latter would be more profitable and feasible, suggesting the bill’s greater impact would be in wealthier areas.

Supervisor Gordon Mar, whose resolution opposing SB50 passed in committee this week, acknowledged in a recent Open Forum commentary that “we in the Sunset District and other low-density areas need to create community-driven area plans to increase density in our neighborhoods: plans to include affordable housing excluded in historical — and historically racist — zoning practices.” That is, trust Mar — and Palo Alto and Beverly Hills — to deal with it someday.

But abdicating housing policy to local officials left California with the least homes per capita on the U.S. mainland and nearly half the nation’s unsheltered homeless. “The question isn’t whether we should build more housing or not,” Mar wrote. On the contrary, that is exactly the question being put to supervisors and legislators, and the answer should be obvious.

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