Gays and lesbos cannot tolerate "transgender", because it asserts that males and females have unique qualities that ultimately draw them together.
Those nuts just wish they were born the opposite sex -- they don't share the gay agenda of destroying the different roles of men and women. Quite the opposite (though by definition they are willing to twist and corrupt themselves in pursuit of their own sexual ideals).
Gays and lesbos hate bi's even worse, because bi-sexuality suggest it is a choice.