heiniunai
I agree that the link's comparison of Tokyo 23 Wards with all of NYC is not an appropriate comparison. But not necessarily because of single-family housing as you describe. Even for Nakano Ward (with population density nearing Manhattan's), 20.8% of residential buildings are detatched single-family homes and 48.9% of residential buildings are less than 3 stories tall [0], surely a higher proportion than several NYC boroughs. Its high density is more due to having fewer areas with offices, narrower streets (compared to NYC), and barely any green space.
[0] https://www.city.tokyo-nakano.lg.jp/dept/505700/d026142_d/fi...
https://japanpropertycentral.com/2021/12/housing-in-tokyo-is...
The 23 wards of Tokyo are 5 times the land area of SF city proper.