If you said "This woman is going out to hang out with little boys" when the line meant "men of below-average height", well, sure, "boys" is perfectly acceptable as a male human term, and they are little, below average in size, but it's deceitful in the context used.
I doubt you'd be getting this pissy if a guy in his 20s said "I'm hanging out with the boys" referencing his friend group.
What's your point?
Context matters.
If you said "This woman is going out to hang out with little boys" when the line meant "men of below-average height", well, sure, "boys" is perfectly acceptable as a male human term, and they are little, below average in size, but it's deceitful in the context used.