I appreciate the attempt to be even handed here, but there is a whole manosphere subculture centered around describing and acting upon women not as equals but as "females" using that language, which really isn't mirrored in the other direction. While you may give someone the benefit of a doubt due to the above, I feel the language is an incredibly strong indicator that whoever is speaking does not speak to many women as equals, or would not be calling their entire sex "females" like one does in an anthropological study.

As for them being grown-ass adults or not, I highly suspect the context would make this abundantly clear if you were talking about people being acting foolish, rather than simply their state of being.