I don't think it's as simple as "not liking trans". There's a bit of nuance to it that unfortunately intersects with the fetishes of others. Basically, from the looks of it, it can be boiled down to two simple but contradictory directions
Group A: Likes that Shauna is a transwoman for character reasons. In this group, Shauna's dysmorphia and her preference for men would make her unlikely to engage in penetrative sex with Jaime on her own volition.
Group B: Likes Shauna because of a preference for women with penises. In this group, the desire is to see Shauna use that penis for penetrative sex with the MC as well as other women. As one commenter earlier stated "why give her a dick if she's not going to use it".
From what I can see, this is the crux of the argument. In neither group is anyone opposed to trans-Shauna, and in fact has a preference for her, but they have very different ideals to how things will play out.
Well I'm a bit in both groups. When I started the game, and the option to make Shauna transgender came up, I was super excited, not because I thought this was basically gonna be a futa game, but because I would mean exploring a transgender character. So far, I haven't been disappointed, I think BrainDrop has really demonstrated some great skill in writing trans people and problems they may face with body dysmorphia and acceptance in society and all that (although, compared to the real world, it is somewhat unbelievable to me that Skye would just be accepted on a male basketball team, no questions asked).
That being said, if BD manages to write it in a believable way, and progresses slowly to it, I am also very excited about the possibilities that this three (or more) person relationship could explore with Shauna as both a penetrative and receptive partner and I really do want that to happen (and here I'm open to all, Jamie being the receptive partner, but also the MC or other girls, whatever, the more the merrier, yay inclusion). I want her to become more comfortable with her body in that way and I think it could be extremely hot, not least
because of the character progression that would be needed to get to that point. But I don't want it to happen just so that we can have some nice futa porn, it has to be realistic.
So yeah, I don't think the people who play Shauna trans can be so easily separated into these two groups.