Ridiculous. First of all I have known several transgender men and dated two of them and I can tell you that this shit was the farthest thing from their minds.
You guys lost my support forever and ever amen with that singular-they horseshit. I see that in a social networking profile and I block the person. "They" is a plural. Stop using "someone" as the subject of statement about people of indeterminate gender and this issue goes away.
Authentically transgender people are about one in 30,000 yet we are instructed to refer to everyone else as "cis" as though we need another excuse for bifurcating people into categories. And I do not count cosplaying transvestites in the same category, they are about the most useless people on the planet.