How an Average Family in Tokyo Can Buy a New (detacted single-family) Home (for about $300k in Tokyo Proper) https://www.youtube.com/watch?v=iGbC5j4pG9w

There's more urban dwelling options than just skyscraper.

Low Japanese fertility appears to be a product of their work culture; you don't have time to go on dates if you leave the office at 10pm.