Ok but that's a different claim than the one I was originally replying to.
And anyway the masculine plural being genderless is a convention of romance languages, which english is not. It is not useful or consistent to describe expectations for english usage in terms of the features of other languages. Negative concord and invariant be are common language features globally but you don't hear white americans scrambling to include them in standard usage.
There are plenty of other situations in English where the masculine plural is gender inclusive (probably because so much of English is borrowed from romance languages). For example, "actors" can refer to both male and female actors, "actresses" cannot.
Identity politics has resulted in certain groups making concerted efforts to try to eliminate such usages, but it's still an ingrained part of our language.
"it" in this case referring to gender inclusive masculine plural nouns as a feature of the English language, not the particular use of "you guys" as one. That phrasing may well be new. Actually it seems like the phrase "you guys" is itself pretty new, see: https://books.google.com/ngrams/graph?content=you+guys&year_...
And anyway the masculine plural being genderless is a convention of romance languages, which english is not. It is not useful or consistent to describe expectations for english usage in terms of the features of other languages. Negative concord and invariant be are common language features globally but you don't hear white americans scrambling to include them in standard usage.