I demonstrated the home ownership is well over 50% worldwide. I conceded that that might well be more condos / flats / coops in other countries, but I don't have that data.
As for single-family being the cheapest to build: that is quite likely true worldwide outside of urban cores. If you think it's not, it's on you to prove it. If it IS true, then it's obviously not a US political problem.
My point about single-family being cheapest to build is indeed a US political problem, because through law/taxation we have incentivized it to be. By cheapest to build, I mean including municipal development charges and the land cost. The external costs of these developments (increased carbon emissions, less efficient land use) are not being paid for by the developer, so taxpayers/local governments are not being forced to pay for that burden.