In Japanese way, being polite means respecting others
Different degrees has different meanings, this way means just a greeting.
We have 3 different ways to bow (informal, formal, and very formal).
Bows can be generally divided into three main types:
The first one is the 45 degree of bowing,
Very formal bows are deeper up to 45 degree angle
this is the most polite way of greeting by bending the waist up to 45 degrees
Formal bow is 30 degree angle
and formal bows at about thirty degrees.
Informal bow is 15 degree angle.
Informal bows are made at about a fifteen degree angle or just lean over one's head to the front.
One is for greetings. Both parties bow when you meet somebody, for example, when you say, “Ohayou gozaimasu”（good morning）.
According to an article I read, Chinese people do not follow the bowing culture anymore because of communism that almost completely westernize the Chinese community.
I think many other countries also do bowing but each county is very distinct they do have that culture that originates from their own history.
Japanese style bowing was a traditional Han greeting gesture. People bow to each other with their hands holding together and reaching forward.
Japan never had this. Their westernization is an addition, not a replacement. They didn't give up their old ways, they just add the new ways as a more fashionable alternative. At least that's how I understand their Meiji Restoration.
But I think the definitive reason that we don't bow to each other anymore is because we had went through communist rule that almost completely westernized Chinese society. Old traditions were despised and threw away. We replaced bowing with hand shaking. It's not a slow culture/custom change, it's a brutal and forceful cut that severs the old from the new. You're considered uncivilized and outdated if you bow while other people try to shake hands with you.