Query -- Scantily Clad

[Baker, John]

        I'm not sure I really see the claimed evolution of the phrase in your examples.  As far as I can tell, "scantily clad" simply means "not wearing enough clothing," and it's maintained that meaning over time, although the phrase seems to have become more common and to be applied more frequently to sexually provocative attire.  I suspect that such evolution as has occurred tells us less about the phrase than about societal mores and changing fashions:  In recent decades, society has allowed women to wear less clothing but has condemned them for it.  When men wear less clothing, however, it's not necessarily seen as sexually provocative.

John Baker