The deadnaming, obviously.
Though what Luke is doing here is not parsing the headline correctly. It says that the police deadnamed him even though he was the victim of the crime, not the perpetrator.
Funnily enough, if he wanted to be particularly thin-skinned about it, he could pull the troon 'It doesn't matter what crime you've committed, you should always gender people correctly' argument out. The headline could be said to be implying that the police deadnaming him would be acceptable if he was the criminal, if you read everything through that bad faith lens that idpol types like Luke do.
But he just didn't understand it, because he's not very bright and automatically ran it through his victim filter. We talk about how his followers are morons for giving him money, believing what he says and all the rest, but they actually are likely all dumber than average.
Some troons are clever, or at least cunning - just think of the number of things a straight white man can do and be celebrated for if they wear a dress and call themselves Samantha, that they would be crucified for if they did it as Samuel. But Luke's followers are all dumber than he is, and he's hardly a thinker. Coom-obsessed retards all the way down.