[sokoloff]

Cars and buildings are probably more loosely coupled than most HN readers imagine. Up through the engine in the 1995 Mustang (I think that was the cutoff), the Ford small block engine line would all bolt into Mustangs all the way back to 1965. I've got a 1989 block, a modern 5-speed transmission with overdrive, hydraulic clutch, disk brakes, dual circuit braking, limited slip differential, and a semi-modern radio in my 1965. All of those were either direct bolt-on or straightforward upgrades with minimal field engineering needed. Many of the VW and Audi engines also have common engine/trans mounts and interchange across years and brands. You can often bolt heavier duty suspension or brake packages onto base model cars/trucks. "Parts bin engineering" is a phrase to search on to learn more. It's done aftermarket, but it's also done by the manufacturers.

There's a similar story in the mechanical engineering for buildings. Sure, some architectural choices will make it harder or easier, but most buildings can be retrofitted system-by-system over the decades a building is in service.

Part of that is to allow configuration pre-sale, but a lot of it is just "it's too damn complex if everything affects everything else", which is not that different from software.