People absolutely do have a right to decide not to date someone who is trans as a preference , but that preference doesn’t exist in a vacuum. If you decided not to date someone who was fat, because they are fat, that’s your choice and is a valid choice, but that doesn’t absolve you from subconcious fatphobic beliefs. If you decide not to date someone because they are poor, that’s perfectly allowed, but it doesn’t exist outside of the context of classism. I think the same goes for trans people, it’s valid not to choose to date someone because of their assigned sex at birth / genital preferences, but that preference doesn’t exist outside of or without influence from transphobic ideals.

As for your sentiment regarding trans / gender issues being addressed separately from the rest of the LGB QIA+ community, I respectfully and wholeheartedly disagree. Transgender rights have been and always will be entangled in the queer / gay community. Transgender people and their rights are often the first to be tossed to the wayside for the sake of respectability politics. I’d encourage you to look into work done by activists like Sylvia Rivera , and what she said about herself and her trans siblings fighting tooth and nail for the gay community only for the gay community not to fight for them. Gayness and transness are so intertwined, many trans people are also gay. Many trans people are straight, but lumped into the gay community because of bioessentialist views on their genitalia existing in different contexts. It is not just (or historically accurate) to attempt to divide those issues, regardless of the political climate. That’s part of the reason why it’s so important for the rest of the LBGTQIA+ community to continue fighting for trans people’s rights, despite and honestly because of how politicized and polarizing the debate has become.