A mother of one boy & three girls just made this joke in my company. Her son was also in earshot. In fact, he wanted to tell it - he thought it was hilarious.
So, after he told it a second time, I enquired with him:
ME: This style
HIM: This style
What will you be in a few years?
I don't know...?
Well, you're a boy now - what will you be in a few more years?
Ohhh I'll be a MMMMAAAAAANNNNNNNN! (playfully flexing his nonexistant biceps)
Yeah - will that joke still be funny to you - what does it say about you?
It says that women don't like me, and I'll die early - but who cares...
Point - set - match.
The kid thinks it's funny now. But, I'm hoping in a couple or so years, he'll think about this and it will start dawning on him... slowly, but surely.