I've been seeing a lot of discourse about the Murderbot casting, to the tune of "Wells says she imagined it as brown"/"the narrator of the audiobook is a man"/"the writing just sounds female, the types of things it notices and cares to mention and the way it puts its sentences together is how a woman would"/"it's canonically agender wtf"/"agender people can look masculine you asshole"/"it's supposed to look big and average that means white male"/"that's your own cultural bias in play and evidence says the average in its universe is brown"/"that's your bias in play there's no ironclad indication what the average is in the Corporation Rim"/"here's every single canon description of Murderbot it has no canon physical attributes other than Tall it could be played by literally anyone Checkmate Atheists" etc etc etc and it all just... misses the point?
No one is annoyed with Skarsgård!MB because "white dude" isn't canon.
They're annoyed because written Murderbot presents a level of identification and recognition for them that "white dude" does not.
Or, in other words: it is difficult to imagine a level of abuse more profound than not having the freedom of your own literal thoughts, consigned to a cripplingly limited and cruel social role from which any deviation is met with brutal pain. And it is all too easy to imagine a demographic who are presumed violent, hostile, and inferior, good only for labor and violence, who must be controlled and denied and unpersoned for the good of the rest. The lines aren't hard to draw, here; Murderbot is deeply relatable to many people who are not (visibly masculine) white men, specifically because they are not (visibly masculine) white men. Because they share with it the experience of oppression, marginalization, and being known on sight as wrong, being punished for the slightest deviance. Because it is not just another in the long boring line of ten thousand thousand grizzled white space marine heroman types; it is the thematic opposite of that.
And yeah duh obviously you can look like a boilerplate white dude and still suffer plenty of oppression, but film is a visual medium. Character design is a crucial part of its language, especially when a specific character is the only example of its type available to the audience. It is a shorthand that the audience will understand as a reflection on the wider setting. Which means that casting Skarsgård is, whether they meant it or not, a subtle statement that the ultimate bigotry in Murderbot's universe is against and about conventional white dudes.
Or in other other words, you cannot refute complaints about Skarsgård!MB with ~canon~ because canon has nothing to do with it. It's a thematic inconsistency, a failure to understand the not the story's text, but its subtext and its place in the wider cultural conversation of sci-fi (or at least to accurately translate those meta considerations to the satisfaction of a decent segment of the audience).
Like you can still yell about how bullshit you think that is if you want. Casting's not that deep or it's an important queer metaphor to pass and still struggle or people have no inherent 'right' to representation or whatever else. I'm not telling anyone what to say or believe. But just understand that that's what you're actually arguing with (or for, for that matter), is all I'm saying.