> the literal definition of guys is: Persons of either sex
I'm no culture warrior, but this isn't accurate at all. That's a definition, but it's not the usual one - ask someone "how many guys have you slept with?" and see how they interpret it.
To me, "guys" is the rhetorical equivalent of a code smell. There are cases where is obviously innocuous, like saying "hey you guys" to a mixed group of peers. But when the CEO says "I want to congratulate the guys on team xyz" in reference to a team with one woman... at minimum we can say his intent is ambiguous.