I can only really speak for myself here, but I want both. Like I want to be physically female, to the point where I could be a biological mother. Unfortunately, that's not possible at the moment, but I'm going to try my best to get as close as possible. But even though I say "I want" it's not actually a choice. Before I started taking estrogen, I was very depressed to put it mildly. If I stop taking estrogen, I'm pretty sure I will feel the same way again. None of this has anything to do with my gender. If I live in a society with no gender, assuming such a thing is possible, I would still have the same medical needs. But I also want a certain gender expression. It doesn't matter that gender expression stuff is socially constructed. There's lots of other things people want that are socially constructed, self actualization is a basic human need.

There are some trans people who medically transition and never present differently. It's usually trans women who start hormones as adults (sometimes they call themselves manmoders). I've talked to people who have done this for like a decade. After they take estrogen for a while they look pretty feminine, but most people don't really know what a male on hormones looks like, and so with a short haircut you can probably present as a man forever. In theory, these women as a test of someone who wants to transition their sex but not their gender. However, my sense is that most of them aren't very happy about their situation. The reason they present as men is because it's not safe for them to do otherwise, because they're still figuring out how to go about socially transitioning, or because they're afraid of looking like one of the horrific caricatures of trans women that dominate our culture (which, yeah, I'm afraid of that too).

So, ideally, there would be no gender, right?

I'm really out of my depth here, but I don't actually think gender abolition literally means that there should be a society where a person's sex carries exactly social or cultural implications of any kind. I think it's more about how sex-based hierarchies are bad. But none of that actually matters for trans people who exist today, because it's a goal or an ideal. If you go outside, there are gender roles alive and well right now, and sometimes we have to go outside. Expecting trans people to somehow live without gender or whatever because that's what you think society should be like is like expecting a communist not to own a smartphone.

Actually, I can imagine it helping in an ideal world, but in our fascist reality that will probably just end up genociding people

This is exactly how I feel about it. Lots of people disagree, but I definitely didn't act like most little boys as a child, and during puberty dysphoria just kind of destroyed my life. If you believe that a person is their brain, as in materialist monism, then some feature of a person which causes major effects on their life would logically have to exist as a physical structure or process within the brain. Assuming the brain scan was good enough, there's no actual reason why you wouldn't be able to identify this structure or process. However, I hope the scans never actually get good enough. Pre-natal testing has largely eliminated babies with Down Syndrome from many European countries. I used to work with some students with Down. They had major difficulties with some things, but they were also perfectly capable of understanding lots of stuff and are generally very happy. Sometimes, I would think about what it would be like to explain to them that they may be among the last generations of themselves who will ever be born. It's kind of horrifying. I don't trust cis people not to pull the same thing on us.

Books? I guess Whipping Girl by Julia Serano.