While I did not read the entire thread, I guess I'll give replying to these a shot.
Please keep in mind that I'm rather clumsy and uncomfortable with writing one-piece text posts and am much more of a chitty-chat person, so I might be missing some points to address or not make the conjunction as apparent as I should in some cases <_<
First off, I will obviously be speaking from my own point of view, as somebody who's affected by this and considers herself female: Now, this is my self-consideration and image, because I feel it resonates with me - how exactly, god knows (..or rather doesn't), but what I mean by it is that being referred to and viewed as female by people I know is the only way of reference that comes natural to me, read: "not forced in accepting as a reference to me and who I am", if that makes any sense.
Childhood Trauma:
Hostility is a very common thing towards anyone who's breaking out of the box that is considered "normal" or "proper", and a presumable guy raising their voice to be seen and treated as female will logically get a lot of frowns and, in many cases, distrust thrown at them and so people will natural keep their distance or show presumably-negative patterns around them, even though they may solely be wondering about what exactly is the matter; now, while in itself and for a moment, this doesn't do all-too much, people tend to get into that routine of "othering" one that is in such a situation, and walking up to them in an attempt to solve that will also often be taken as a rather offensive measure - keep in mind we're talking childhood or teenage here, so people are not exactly fond of being told that they basically got your entire point wrong and should please reconsider what you told them in another way that is practically "dictated" to them. They lack the understanding because it's an alien concept to them, because schools like to keep it in the closet and grave and whatnot else hidden wherever they can because it'd mean confrontation and -obviously- outraged parents, mainly religious ones at that, and as we all know religion is a very special good that the state seeks to pet and caress wherever possible and "no believe is wrong" and all the other relative moral crap.
Needless to say, many parents aren't exactly more educated than the other bullying children at school, so it shouldn't be a surprise that many a "trans"folk suffer from abuse at a consistent rate and all-around the clock; that is, speaking from my own and friends' and acquaintances' experiences - sure, there are ones that find themselves in a good place aswell but since we all know how practically neurotic our dear society and state are, that should come with no surprise; it's not like child abuse was a very unexplored ground around here, either, so you can simply see the "trans" aspect as an additional kicker for the already-pissed off parents and suddenly it all makes sense.. <_<
Gender/Sex and Patterning:
Firstly yes, sex is considered as only the physical reproductive and secondary sexual traits of one's body while gender is the "all around that society makes it" - we are given the sex and we are taught the gender, so to speak.
Now, does that mean that gender is a set framework that you have to strictly operate in in order to consider yourself either male or female? Obviously not - nobody would really consider an unshaven overweight tomboy as particularly feminine for as far as society's education goes, but yet you wouldn't argue that they are female, would you? For that there's mostly one common belief or form of reasoning behind it: people go by another's (obvious) sexual characteristics, simply refer to the person in question as female due to them apparently being equipped with a pair of breasts and a lack of a penis, then widening the "gender" aspect for themselves subconsciously due to their "sex=gender" belief, now including not only what education and media told them but also what they saw with their own eyes and inflating both categories.
With that natural inflation of to both of the classical sex and gender norms we'll eventually arrive at a point where ambigious or opposite-sex characteristics will still perfectly fit in what was originally "designed to be the opposite" (which is where I believe the entire agender/fluid comes into play), making categorizing people harder by the day and nurturing the common mindset that "trans"folk are "trapping" the average white male people around them into believing they are something that they "are not".
As a natural sign for those considering themselves "trans" you will also obviously find a heightened interest in what is considered the "exclusives" among the two classical genders of male and female, by your example, "sexy dresses, heels, makeup (for MtFs)" - where this motivation ultimately comes from varies by person, just as it would with the average "cis"people; I for one really enjoy relatively high heels because I actually find them natural to walk in (speaking 6-10cm), so implying it's "for the sex appeal to overcome internal issues" sounds to me like you'd question every sneaker wearer's running speed because they /obviously/ seek to overcome it by footwear (I'm not meaning this to sound offensive, I'm just trying to make a direct comparison for what I get from your post) - sure, there will be people that wear sneakers because they like to run or feel like it makes them better at it, but there'll also be people that do it just for the comfort, which I would argue makes up for the largest part of them, actually.
As far as "doing all those things to alter other peoples' perspective of them" goes.. no.
That's actually a rather uncommon thing, at least for the people I conversate with - for me it was this simple: I felt like things about my body were off at like, the age of 4, and I'd argue I was a rather intelligent child (then again, who wouldn't..). I didn't want to grow up and be tall like my father, I didn't want to grow a beard and I didn't want to have a penis - I wasn't exposed to the entire sex ED and whatnot or gender normes and behaviouristics at the time but I felt I needed those things to change and to prevent them if that was possible in any way, and I voiced those concerns. Needless to say, the feedback was rather.. discouraging, but I stuck with it, because that's how I honestly felt.
Another thing about hormones is also that they are not "just there to please others" (and really, hearing those things is like.. rather offensive to me, to be honest :/) - they do a whole lot of things; firstly, I really really love the farm and fuzzy feeling of growing breasts, knowing that my skin's getting softer and all that other stuff, and I really wouldn't want to miss it. Secondly, estrogen and testosterone are not just responsible for how your body looks and feels but also how you operate and feel - as an example, I always felt horribly lethargic while on testosterone (or, well, without HRT), and that's a very common thing for "trans"people - their birth-given hormones are doing exactly what they shouldn't to their psyche and while I do not have any scientific proof for that, I can say that is honest how it feels; getting on estrogen has made me feel a lot more at ease about my body, enabled me to work things out more calmly and whatnot. Sure, that's also not a thing applying to everybody out there, but so is for just about anything, isn't it <_<
Now, I'd like to give this a(n even more) personal note by saying that I honestly do not enjoy reading all the "scientizing" about the whole topic because I feel a lot of people take it too far and reduce "us" to just a pile of neurotic and delusional symptoms.. yes, there are delusions within the "trans" community, yes there are neurotic people, but so are they everywhere else in just the same relative quantity, so I do not think that that is what one should focus on; then again, I view this from an interpersonal perspective where I want people to pay an equally decent amount of respect to "us", so that's why I'm making all those comparisons - I honestly don't feel like "trans" people are any special or different from "normal" ones on any personal level whatsoever; people are people, whether they have a less common deficiency than the others or not..
** Sorry if I ended up writing a lot of unconnected jibberish, walls of text make me kind of wonky <_< ** Oh yeah, if you have any specific questions, go forth and ask them at any time, I guess **
