"It's time to dump the tired argument that density and height are green and sustainable," says the generalizing headline for a post by Lloyd Alter at Treehugger.

Alter argues that density drives up housing prices and harms the environment because massive luxury skyscrapers attract the wealthy. Which is extreme to the point of absurdity—that the pinnacle of density represents the entire issue. It's like arguing we should ban cars because some vehicles are Hummer limos, or condemn gay sex because some guys contract HIV. Yet it's the basis for his call to arms:

It's time that the NIMBYs demanded an open and transparent approval system where the rules mattered, where height limits weren't where you started but where you stopped. It's time that the nostalgists for an era when working people could afford a roof over their head demanded the same for the current generation. Its time that we thought not only about what we are building but for who.

In reality, the vast majority of construction—dense construction—will never be luxury skyscrapers regardless of height limits. This battle cry is particularly nuts because many NIMBY (not in my backyard) activists protest almost any new construction (it's inherent to being a NIMBY, they oppose whatever's close to them). Their involvement in permitting processes frequently amounts to attempts to block construction completely. In Seattle, they're often dead set against buildings a mere six stories high.

Alter's focus on skyscrapers as the lightning rod for an anti-density crusade is particularly off-point in the context of creating affordable housing. Most dense buildings of four eight stories absolutely create the sort of housing stock that is affordable or becomes affordable with a decade or two of wear, and it contributes to a city that has a smaller carbon footprint than sprawl and promotes a thriving street economy. It's the NIMBYs whose plight against density freezes construction, making housing scare by driving down the relative housing availability in a growing city, and thereby driving up prices and promoting sprawl. Scattering people into remote suburbs is what's unsustainable. Alter's argument might make some sense if cities were all skyscrapers—but they're not, so it's ridiculous.