It would really depend on the level of transphobia, and how much I felt it related to the music itself. If it was something particularly awful, it might give me too much of a negative association with the music, and I'd certainly be put off supporting them monetarily... but overall? Probably not.
I expect that, if pressed, many of the members of bands I listen to would have somewhat transphobic opinions, since transphobia is so depressingly common and accepted. Especially since I listen to a lot of older bands with older members. But, again, it probably wouldn't make me stop listening to their music unless they clearly had a bee in their bonnet about trans people and went out of their way to try and make things worse for us.
I mean, at least half the artists I listen to have already said other things that offend me or that I at least find stupid. I'm usually able to separate that from their music in a "Love the art, not the artist" sort of way. I'd love to only be able to listen to music produced by people whose views never offended me, but unfortunately that would be limiting myself to a pretty small list... and probably ever shrinking, as I expect some of the people who haven't offended me yet have just been better at keeping their mouths shut.
