Yes, being on the gay scene I see quite a range of presentations of identities. Some people may dress / behave in ways more typically expected for the other sex but are quite happy in their identity as gay women or men, others have transitioned and consider themselves straight. (I'm not trying to conflate sexuality with gender identity, but the reality is there can be a lot of crossover)
I also know some that have transitioned and before transitioning were attracted to the opposite sex, and after transitioning they are now attracted to the same sex (ie. the object of their attraction remains the same but of course they are gay/straight depending on their own sex identity), but mostly it is the other way around.
In my role I occasionally work with older teenagers who are transitioning or in the process of trying to, and they are all from female to male at the moment. They are all lovely people; one I'm a little concerned about as they have ASD and other difficulties including a traumatic childhood, and I can't help but wonder if they are pinning their hopes on this as an explanation and solution for the complex feelings they have.
As a gay woman at age of 41 I do look at them and wonder if they had been growing up 20 / 30 years ago would they have been content to express themselves as more tomboyish lesbians, but you can never really know what someone's own personal experience is.
And I have another friend who is in her mid 50s and has accepted her biology reluctantly, but who looks at youngsters today and only wishes she had the opportunity to be young again - she would have transitioned in a shot, but wouldn't now due to health concerns. She has struggled to have intimate relationships because she feels at odds with her own body - I guess that might have been different for her had she transitioned at a young age.