Earlier quoted context omitted.
According to dictionary.com, the definition of "guys" is "persons of either sex; people" The definition of "folks" is "people in general" I'm not sure what point you are trying to make here.
Dictionary definition aside, the colloquial meaning of "guys" is quite frequently "men". I think the GP was trying to be gender-neutral. I actually have tried to move to "folks" myself for that reason.
I'm not saying there's no reason to reconsider language choices. Frankly, I agree overall that this phrase and its derivatives should probably be slowly retired, if only to avoid the occasional confusion. My point is only that even in colloquial usage there are patterns involving "guys" that are clearly gender-neutral at this point and have been for decades.