this is over-the-top ridiculous.So you’re defending your professional identity by making vague homophobic and transphobic remarks? Seems like a winning strategy.
"institution as ancient as 'marriage' " Is not in any way homophobic. Maybe the poster is...but no one could tell by this comment. I mean..really. It is complicated subject, but someone that may be religious and believe that marriage is an ancient ritual with religious roots (and may even think they have historical context and background to prove this point) doesn't say anything about their feeling towards someone who has same sex attraction, nor about what that person feels about the governmental rights they deserve if they form a union with their loved one.
"or the identity of male and female is completely up for grabs" - this has NOTHING to do with transgender, trans-whatever. How can you say that the poster is scared (phobia) of transgender people based on this?
Isn't ridiculous generalizations the problem? Why are you making them then?