I agree with this on premise. But the US in particular (though Australia and Canada both share quite heavily in this), makes is practically illegal to build non

I agree with this on premise. But the US in particular (though Australia and Canada both share quite heavily in this), makes is practically illegal to build non-detached housing, in 99% of the country, once you included zoning requirements, parking minimums, set back requirements, community review boards, bans on multi-unit housing on a plot (so that even a duplex, triplex, etc are illegal even if they otherwise fit with zoning requirements).