ZeborahControversial opinion: at least in some dialects, "guys" is definitely gender-neutral, but only as a de-emphasised component of a complex plural pronoun.
Eg "Look at those-guys", with emphasis on "those" and no variation possible = gender neutral
but "Look at those guys", with emphasis on "guys" and option to say "those three guys" or "those young guys" or whatever = male
*you*-guys = gender neutral
you *guys* = male
*us*-guys = gender neutral
us *guys* = male