Article URL: https://laxmena.com/same-capacity-less-throughput Comments URL: https://news.ycombinator.com/item?id=48885138 Points: 17 # Comments: 8

My book club is reading Abundance by Ezra Klein and Derek Thompson this month. The core idea fits on a napkin, so before the meeting I decided to actually check it against real data. Here's what I found, and where it fell apart. Housing, clean energy, cures for disease. The inputs to all three haven't really moved. Money's there. Technology got cheaper, not more expensive. Roughly the same number of people know how to build this stuff as always did. Over the decades, every time something went wrong, somebody added a valve. A highway almost bulldozed a neighborhood in the '70s, so now there's a checkpoint for that. An environmental study got added in the '90s. By the 2000s you needed a public comment period too, sometimes more than one. None of these were dumb decisions in isolation. Each solved something real. But stack enough of them and the pipe might as well be shut, even though nothing on the input side changed at all. Klein and Thompson call this chosen scarcity. Anyone who's inherited a legacy codebase already knows the pattern under a different name: unaddressed technical debt. A pile of individually-reasonable shortcuts, left unrefactored for so long that the system's throughput has almost nothing to do with its actual capacity anymore. I liked the idea. I also didn't fully trust it. So before the meeting, I ran the numbers. I compared two U.S. cities that get cited constantly in this debate: Austin, which started clearing its own valves out around 2015, and San Francisco, which mostly didn't. The gap is not small. Austin permits roughly 18 new homes per 1,000 residents every year. San Francisco permits about 2. Eight times the throughput. Same country. Same everything, really, except the rules. I ran the actual arithmetic using an elasticity number borrowed from a housing study out of Auckland, New Zealand, where a comparable policy change happened and got carefully measured.