For what it’s worth, the topic has never been whether “you guys” is “masculine” but whether it can refer to groups of mixed or not-all-male gender. I do find it odd you have consistently avoided ever making a statement about the gender makeup of groups to which the phrase can refer. I believe it is possible for the phrase to be masculine in a sense and for it to still refer to mixed- or arbitrary-gender groups.

Can you confirm without ambiguity whether you are indeed talking about the same topic as me?