I've often pondered about how Vulcans view gender and sexuality.
I think pre-Surak/logic, they may have demonstrated homophobia and transphobia, but modern Vulcan Society would probably be chill with it under the reasoning that discrimination would reduce a person's efficacy as a functional member of Vulcan Society. For instance, given a choice between allowing a person to contribute verses driving them to the brink of suicide, Vulcans would probably tend to lean towards the first option.
There could very well still be stigma (Vulcans are far from a perfect society; some may have views that it is illogical to have a romantic relationship without a child), but it's dampened by the logic from the previous paragraph.
There's also the Pon Farr to keep in mind. Not only would it be hard to fight a person in the Ponn Farr, but also you'd literally be killing them by trying to prevent expression of their orientation.
There's a gay Vulcan character in the New Frontier book series (U.S.S. Excalibur). From what I recall, there were no social issues but the guy's father disapproved due to "a waste of good genetic material" :-)
It's worth comparing this perspective to Spock's view in TWoK that Kirk not fulfilling his "first, best destiny" as a starship captain is also a "waste of material". In other words, Vulcans place value on a person expressing their truest and best self. That would jibe with the idea that Vulcan society would not place artificial barriers to people expressing their gender and sexual identity, since doing so would be viewed as a similar "waste of material".