First, he didn’t survey “men.” He surveyed “undergraduates.” A group of young adults who are notorious for their gullability, and eagerness to be manipulated. Not to mention stupidity. Not at all representative of the human species.
Second, he presumes, probably with absolutely no reasons whatsoever, that being told your survey results are “feminine” will make men feel insecure about their sexuality.
I suspect there are many, many more errors in his work.