they've been arguing about malgendering on twitter so here's the truth from me, the arbiter of truth (jk but ive been talking about malgendering long before it became a popular buzzword and heres my understanding of it)
malgendering is a form of transphobia wherein a transphobic person uses their victim's correct gender to harass or demean them. it is meant to be the inverse of misgendering, where a transphobe uses the victim's incorrect gender to harass or demean them.
misgendering towards trans women can be as simple as "youre a man." but malgendering is more insidious, like someone saying "you really are a girl" when she makes a mistake in order to insult her intelligence. the phrase "you really are a girl" is positive when removed from the context of the trans woman making a mistake and the transphobe's sarcastic tone that implies shes stupid in an misogynistic way.
if a trans man does something like standing up for himself against an unfair situation or asks for better accommodations/treatment, and a transphobe wants to use that to imply he is selfish and entitled, they might say "trans men really are men" which again, is a true statement on its own. but in the context of the situation, its clear the transphobe is using the stereotypical worst qualities of men to insult and undermine someone's very identity.
malgendering can be any severity of harm, just like misgendering. my mom slipping up in the first months of my transition and accidentally calling me "she", and a bigot shouting "YOURE A WOMAN YOULL NEVER BE A MAN" at me are both examples of misgendering, but one is much worse than the other and its the same with malgendering. being told "trans men are the men of the trans community" as an insult is annoying and rude but not a big deal. however, right now ICE is torturing trans men in concentration camps by forcing them to do pointless and grueling labor. and when they become exhausted, theyre told "I thought you were a man. if youre really a man this should be easy for you" these are both examples of malgendering. one is a microaggression, the other is literal torture.
malgendering happens equally to both trans men and trans women, its not something that is unique to anyone because it is a form of transphobia. the strategy is that if a transphobe tries to make a trans persons life as their true gender so miserable and unsafe, detransitioning seems like the safer and happier option. its psychological torment, moreso than the plain and obvious insult of intentional misgendering. so dont let it happen, call it out when you see it and dont be fooled by transphobes trying to erase the context and be like "what!! what i said was true!"