From Yang Mi and Mao Nan to Olympic champion Gu Ailing, no one can escape MBTI. What magic does it have?
Take a friend around me who likes mbti as an example. It seems that her cognition of everything is to get the truth about why a thing works like this, rather than sticking to the thing itself. After knowing why ta thinks something like this, we can deduce what ta might think at ordinary times. Know yourself. Knowing mbti is probably a way to know what I'm thinking, such as when I'm thinking about how to deal with a thing. I will use my previous experience (si) and classification (ti) to think and find out my own ideas more clearly, which is quite interesting.
For people who are good at observing and summarizing, it is an efficient information system, which can recognize themselves at some time and guide life decisions. For example, I'm entp. When I was confused about life, I knew that many ENTPs had gone through such a struggle stage like me and got out of it. With the pain and confusion with different appearances but the same essence, I can better understand my present situation and inspire some future developments. Generally speaking, it has certain uses. After all, many people and companies have the need to classify people (others and themselves).