Japan has one of the lowest birthrates in the world. This is inevitable as demand from the elderly outpaces young people to fulfill it.
Presumably though, as tax revenue falls due to citizens retiring, that will lead to more privatization of services as the government won't have the money to buy them, and a consequential push towards automation as service providers try to lower costs. If automation happens quickly enough it's not outside the realms of possibility that Japan's aging population could lead to fewer jobs in some sectors.
[0] https://www.google.com/search?q=japanese+birth+rate&rlz=1C5C...