This reminds me of the old Queer Nation Street chant, "Don't Panic." Sounds to me like he needs to stop panicking. Nobody values him less because he's a cisgender gay man. Nobody's asking him to stop being a cisgender gay man.

Cisgender gay people are not threatened by transgender people. Obviously. Cisgender gay people dominate queer clubs, dating apps, and certain other social spaces — just by weight of numbers.

Sharing, as most of us learned in kindergarten, doesn't actually hurt. What's he worried about? That he won't be able to get a date? That he won't have fun places to socialize in?

Perhaps he should open his eyes, look around at reality, and realize he's panicking over literally nothing.