I agree with the basic argument that a big chunk of fandom tends to be very ready to hate white, straight male characters - essentially for being imperfect while white, straight, and male.

That said, I am someone who has a disproportionately large percentage of white, straight male faves - many of whom are characters that it is very popular to hate on. And I still strongly dislike Luther.

I don't think he's irredeemable (whatever that even means), but he's unlikely to be a character I ever fully warm to. And that's because I find him controlling and self-righteous and...paternalistic, basically. And it's an entirely logical bit of characterization for him to be the sibling that most clearly mirrors behaviors he learned from his "father." But I just have no patience for "I know best; I make the decisions for everyone and I'll enforce them if I need to" type characters.

I might have a little bit more patience for him if he were gay or female, because at least then his domineering attitude would be a bit of a subversion of standard character tropes. But even then I think his bullshit would get old really fast.