People shouldn't change in real life. Like when women get married. That is ridiculous.
However as an adult we have the right to change our names for other reasons and several I know have changed their first name, usually just once, but there are exceptions. I've changed both my surname and middle name. And I'm never called my first name.
They let me change to a third PC name because people kept confusing me with another guy. So it was nice they made that exception. But I have never really changed out of "Jim", so that is a constant.