Why do many people still think that the Japanese emperor has real power?

Just like some countries in Europe had kings and popes in ancient times, now the Japanese government is like a king and emperor, like a pope without real power, similar to religious belief. In modern society, there is another system. In the long run, it will actually increase the instability of the country, and the most serious situation may even lead to the division of the country (but it depends on how the leaders at that time handled it). Although the possibility is small, why not put an end to it?