That's the point. It wasn't. There weren't any trans women mentioned or alluded to in the epitaph, and the person assumed to be was not "dehumanized". I'm honestly puzzled by this.
I would be much more sympathetic to the removal of the poem if it weren't over an obvious misunderstanding (or deliberate misreading) of it.
You are blatantly wrong. Sleeping with a woman, and later finding out that person is "actually a man" has been a common trope for the last 20 years that degrades trans-women (see Ace Ventura, Always Sunny, Jerry Springer, etc. I really don't think this is up for debate