I never add comments to posts, but this is an issue that is very near and dear to me so I can't keep it in the tags. If you identify with any of the above comments, but feel scared or unsure, or if saying "oh I can just be a different gender/sex" feels too simple and yet overwhelming, read on.
I'm a bisexual nonbinary engineer. I like things to be able to fit into boxes. It took me a LONG time, a lot of experimenting, and a lot of therapy to become comfortable with the fact that I can't fit into a box.
...Or rather, I can't fit into a box in the way that most people, including other trans and queer people, define the box. But look, I can break it down into different, SMALLER boxes, and then I can understand myself better! We just needed more detail in the taxonomy all along! I may or may not be incredibly over the top here, but I hope I can help anyone else who struggles with the undefinable nature of gender and is trying to fit themselves into a box that isn't right. THERE ARE SO MANY MORE OPTIONS THAN YOU THINK THERE ARE.
I think that gender presentation, gender identity, genital/breast type, sexual orientation, sexual preferences, and sexual identity are all just parts of one big Gender Matrix with endless possibilities. They are all different axes on which you can sit in different places. This is certainly not an exhaustive list, but here's an example:
My gender identity is [man/woman/other], my gender presentation is [masculine/feminine/both/mix], my preferred body for myself is [dick/pussy/strap/other] with [discernible boobs/no discernible boobs]. My sexual orientation is [gay/lesbian/straight/bi/etc], I prefer to [top/bottom/switch/side/etc], I prefer my partner to have [dick/pussy/strap/other] with [boobs/no boobs] and [masculine/feminine/both/other] presentation. My identity during sex is [man/woman/girl/boy/daddy/mommy/sir/ma'am/sissy/brat/all/none/mixture/etc].
There are lots of people for whom their identities are simple, consistent, and "make sense" from the outside. They just think "I'm a man, I like women". Or "I'm trans, I am a woman, and I like women". So they don't need to think about the Gender Matrix. They can see gender and identity as 2D or 3D chess. But there are those of us for whom those descriptions just aren't quite right. We don't neatly and easily fall into any of the categories which society has laid out for us. And, as the woman in that one video said, we're out here playing 5D gender chess.
To see how it works, let's break one of the "simple/consistent" cases down with a Gender Matrix level of detail.
A run of the mill "ordinary" cishet man or binary trans het man could be described as "My gender presentation is masculine, my gender identity is male, my preferred body for myself is dick and no boobs, my sexual orientation is straight, I am a top, I am always a man during sex".
We can group that statement into two general boxes: the first part (in purple) is about our own identity and body. The second part (in orange) is about our preferences for ourselves and our partners during sex and relationships.
So what about cis and binary trans gay men? The purple part of the statement stays identical, but the orange part changes. They could be better described as: "My gender presentation is masculine, my gender identity is male, my preferred body for myself is dick and no boobs, my sexual orientation is gay, I am a bottom, I am always a man during sex".
But from there, there's even more complexity which is possible in the second/orange half of the sentence. We know there are gay men who top, who bottom, who switch, who don't like penetration at all. We know there are gay men who prefer feminine terms during sex, there are daddies and boys and sissies. We know there are gay men who prefer only dicks and no boobs, there are those who don't mind the genitals and/or boobs as long as the presentation and identity is masculine.
And we know that there is more complexity possible in the purple/first half of that sentence, too, even if we hold the second half relatively static. We know that there are gay men who present more feminine. We know that there are gay men who like having a pussy. But they are still men, and still gay men.
For a different example, we can think about men who prefer to be topped by their female partners: "my gender presentation is masculine, my gender identity is male, my preferred body for myself is dick and no boobs, my sexual orientation is straight, I am a switch, I prefer for my partner to have a strap sometimes, I prefer feminine identifiers during sex"
So far, these are all possibilities which I think the queer community on tumblr at least are generally aware of. (I may be very obviously labeling myself as a queer person who has been here since 2012 and has seen the rise and fall of many different "metas" of general consensus among the chronically online). Side note that of course there are people fall off of believing in the Gender Matrix at different points. Homophobia and transphobia all have their own ways of intersecting with the Gender Matrix. But we aren't talking about that right now.
So let's get into the 5D chess. What if I told you that you can have ANY COMBINATION of the attributes within the Gender Matrix? You can be a man during sex and a woman at other times, or vice versa! You can be a woman who is also a man who likes to have sex with men! You don't NEED to completely physically transition in order to find people who will have sex with you in the way that you crave!
Of course there's nothing wrong with transition! But if the idea of being a different gender all of the time, in every way, doesn't feel right, there are other options. You don't need to make sense to everybody. You can find the people who get it and will see you as you see yourself, without having to make yourself fit into a box.
Here's my example: My gender identity is nonbinary, my gender presentation is feminine but like in a kind of butch way, my preferred body for myself is dick with discernible boobs (but pussy is fine for now). My sexual orientation is bi, I prefer to bottom but sometimes switch, I prefer my partner to have any combo of genitals and boobs with generally masculine presentation (although presentation matters less to me than attitude). My identity during sex is boy/sir/etc with masculine pronouns and terms.
I use they/them pronouns whenever I can express them, but I typically get she/her'd by strangers. I generally look like a woman, if a kind of butch and definitely queer seeming one, to people on the outside. I took T for a while and liked having my voice drop, but didn't like having facial hair come in, so I've paused it for a while.
Since understanding that I was Not Just A Woman, I explored my local kink scene and tried a bunch of different ways of having sex and BEING during sex. I realized that I could be pretty much anyone that I wanted to be during a scene. The right people (mostly my other queer and trans kinksters) would see me however I asked them to, and wouldn't judge or question. The cishet kinksters had some more questions, but were generally still very understanding. Because in general, we were all embodying different parts of ourselves during kink and sex.
For me, I was never comfortable with the idea of being A Man to the entire world. I don't want to be a man with my coworkers. But I want my boyfriend to see me as a man, and refer to me as such. And he does!
This is not because of anti-masculinity on my part--trust me, I've spent a lot of time examining my internal -phobias and biases and anti-s. They aren't guiding my choices.
I just know that I don't fit into either Man or Woman, consistently, in all circumstances. Which is why I consider myself non-binary. BUT, I still tend to identify more with womanhood, except in the realm of romantic and sexual relationships. So I let strangers see me as a woman, those who know see me as non-binary, and the chosen few see me as a man.
And that has made me very, very happy.