Basically, yes. You're actively choosing to ignore the context of how that particular scene relates to the rest of the movie in favor of getting outraged about it. There's nothing wrong with your finding it in poor taste, but unlike the other scene(s), it was actually quite relevant to the story.
It can be both relevant to the story AND transphobic. That's the point I'm trying to get to. Saying that it's not because it's "how the story was unfolding" is a very weak defense of something when it's fiction and can be written to unfold in literally any other way that doesn't put Ace in the situation of having to strip down a trans person so a group of people (and the audience) can laugh at the half-naked trans person on display - something which, itself, needs to be put into context (since we're talking about that) of the long history of similar things in both media and in real life.
I can understand you being uncomfortable with a scene that hits a little too close to home, even if the scene was not executed with the same intent as the real-life scenarios you mention. However, similar to veterans with PTSD being unable to watch Saving Private Ryan or other movies that allegedly recreate battle conditions a little too well, that's not a movie problem. That's a you problem.
And? I never said it wasn't a "me" problem. I don't expect the world to adhere to my needs. I don't have a problem with people watching the movie. I don't have a problem with people enjoying the movie. I don't imagine that every person out there as in tune to issues of LGBT representation in media as I am and that's fine, but to argue that that scene - crucial to the story or not - was not transphobic is baldfaced denial and/or willfully missing the point.
tacitly supports trans people deceiving others by not disclosing such. If real people are having this reaction from partners, then there is a problem as an informed partner wouldn't behave that way. That is where my questions about the mens' rights, preferences, and how forcing such on them came in, as that seems to be in direct contradiction to equal rights goals of the LGBTQ movement.
What I was referring to with the ""Ace and those guys slept with a trans person HAHAHA SO GROSS AND FUNNY" is denial given that exact thing is something trans people actually do experience." comment was, quite literally the furthest thing from that. The joke makes light of the fact that media like this reinforces the fact that it's okay to see trans people as something disgusting, where people being sick after finding out that someone they were attracted to five seconds ago was trans is an okay gag to resort to for cheap chuckles (see: the episode of Family Guy with Quagmire's dad, the Academy Awards dressing room but of The Naked Gun, etc). You don't even have to be in a relationship with someone to trigger this kind of revulsion in some parts of society - simply walking down the street is enough for some trans people to get dirty looks or worse.