> one study found that 77% of trans people surveyed identified as gay, bi, queer or something else other than straight.

I question a 'study', that is nothing more than a pie chart with no source material, with their link going to a dead site. There are interesting studies and articles about the change of sexual attraction of Trans people during HRT and before/after Bottom Surgery that are more than just one pie-chart.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4192544/

https://www.them.us/story/sexual-attraction-after-transition