All I’ll add is that Japan’s boom period in the early 90s was largely based on their ridiculous housing market. They were incredibly aggressive with the lending and sent house prices to astronomical levels. Even worse than US and Europe did a few years later. They’ve basically never recovered from this period and have been in deflation ever since. Combined with the issues you already raised, Japan are not looking good at all.
Yeah if they can’t afford to buy a home anyway they might aswell enjoy themselves. It’s also pointless saving while your country continues to print money and the things you are saving for increase in price. Just go and enjoy your cappuccino and wait until your boomer parents die and leave you something.
I’d say the cause is uncontrolled capitalism that has made housing into a commodity that the average person can’t afford. I think the financial sector reliance on the housing market for growth has hurt the people who actually just want to live somewhere.