No, they're not. They are places where cities go to die.
Walk in Tokyo and try to find children there.
Walk in Tokyo and try to find children there.
There might a few more things going on there than just density, perhaps operating on a national level.
Japan has a declining population, yet Tokyo prices are skyrocketing. Some people now live in "microapartments" where you can cook while sitting on a toilet.
Yet spacious houses are literally sold for nothing but transaction fees, just 2-3 hours away from Tokyo.