A bochor isn’t necessarily a boy. A bochor can be a man.
“only if it’s done one way and not the other, but I find that usually people who do one, do the other.”
What does that mean?
And are you suggesting that married women not be referred to as girls? (As married men are not called a bochor.)
The reason I find it highly problematic for males to call adult females as girls, is that the underlying reason it is used is as as a form of endearment.