The instant I saw this picture, I thought of the Parks and Rec scene:
"That's not really the attitude I expect from an award winner."
"Everything I do is the attitude of an award winner, because I have won an award."
That should be the case for the picture "Everything I do is manly because I am a man." And the same for the person you are responding to "Everything I do is gay/straight/other because I am gay/straight/other." That one part of someone's identity has no bearing on defining the rest of them - ie, being gay means that he's attracted to men but doesn't define what he wears, how he acts, etc.