Yes, but it matters how much it intrudes on your personal life.

Paying social security (and saving for retirement) when you are young, and getting (some) coverage when you are old, is one thing. It's "only" money.

Having your time, availability, emotional capacity, mental health sucked dry by the elderly in your own family is an entirely different thing. Raising small children is an extreme challenge that requires all your resources; young and middle-aged Japanese are entirely reasonable not to start families.

I recommend reading this:

https://en.wikipedia.org/wiki/Sandwich_generation#Other_chal...