Evidence from a number of studies also points to the fact that transgender people are far more likely to be in same-sex relationships than their cisgender peers, negating the homophobia argument completely. The National Transgender Discrimination Survey of 2015 reported’ the sexual orientation of the sample demonstrates a diverse spectrum of sexual orientations among transgender and gender non-conforming people.
Among respondents, 23% reported a lesbian or gay sexual orientation; 24% identified as bisexual. The studyy^ continues:
I think this section is interesting. They are negating the homophobia argument by pointing out that people who transition are more likely to be in same sex relationships.
Now, it's hard to be sure, but I think they mean same gender relationships when they say same sex. Taking their figures, if 47% of transitioners end up gay or bi, the remaining 53% are straight.
But a straight relationship where one person has transitioned is factually a homosexual relationship.
So, given that transitioning doesn't seem to change the sex a person is attracted to, 50% of transitioners by those figures have gone from gay to straight.
Only about 5-10% of the general population are gay, so that's a high rate of conversion to my mind.