> If you want to argue that they wouldn't solve the housing problem in SFH neighborhoods

I am arguing that anyone who blames the presence of parking for housing supply issues has failed to understand both the geometry and scale of the problem (or more likely imo is actively attempting to push an anti-personal-car narrative).

> the road infrastructure alone to get that many cars in and out of the garages would bankrupt Beijing or Shanghai.

I wasn't talking about traffic engineering problems. Only raw square footage for living space. You can generalize the question I posed as - in an alternate reality where every housing unit in (say) Beijing were precisely 10% larger, and total stock were reduced proportionally to accommodate that change, but everything else were exactly the same (improbably, I know) would that make or break the housing market in terms of supply and demand? The answer is that it would not. Housing supply problems are not due to a mere 10% shortage.

> More first world problems and American exceptionalism I guess.

I don't follow? What about my objection to reducing buffer space comes across as "American exceptionalism" to you? And why do you disagree?

It's simply a matter of geometry. Expanding the footprint by a few feet versus duplicating the entire structure upwards multiple times. Obviously that doesn't apply to places that already build upwards to the extent physically possible but since approximately nowhere in the US does that it's neither here nor there.