with regards to the why would you headcanon someone as transphobic?
I'm trans. I meet a lot of transphobes. very often, cis people don't believe me because they always thought the transphobic people were nice. it's helpful to be able to talk about day to day transphobia in fictional characters, because it means a lot of cis people are more willing to see those same actions in real life.
and Martin has a lot in common with a lot of transphobes I've met to be honest. he's the sort of guy that would say he's not transphobic, but that I shouldn't use public bathrooms, or participate in sports. he's the sort of guy who wouldn't use my pronouns because it might confuse someone. he's the sort of guy who'd see me paint my nails and go, oh, I thought you were trans. he's the sort of guy who would over emphasise the pronouns when introducing me to someone, so as to show he got them right, but also immediately out me. and that can be a really harmful person to be near, because noone is willing to get on your side when you call that shit out.
Also wow what a stupid ass take. Dealing with complicated things in fiction is shown to be psychologically healthy.
Hope I'm not misinterpreting this but a lot of people have this view where if they have a favorite character, especially one they project onto, then that means that character is instantly exempt from any harmful traits or behaviours and exists only in the bubble of projection and self-recognition.
And that's fine. That is just one of the ways of engaging with fiction. But it's important to keep in mind that one person's experiences are not gonna be universal and also that exploring difficult topics in fiction does not mean you condone them.
Ultimately none of this matters because fictional characters are by definition fictional. Everyone is entitled to their own interpretation whether or not that interpretation cares to take the source material into account. You can stretch Martin Blackwood thin with your wildly opposite takes on him and none of it will matter cause he is not real and can't be harmed by it. It's just annoying to me personally that half the fandom will delightfully engage with homophobic twink Elias but if you dare to even try doing something similar with Martin you're a weirdo freak and a bad person. Do you hear yourself