Also for reference, these are "compound nouns" - a single noun composed of multiple words. No one has these issues with "ice cream", for example, but "you guys" really is just another one of these.
I think it makes sense to say "you guys" is a compound noun, but the word "guys" can be used in this gender-neutral addressing-a-group sense outside of the phrase "you guys". For example: "Hey guys!", or "Guys, what should I eat for lunch?"
