McConaughy isn't the only example of this phenomenon. Much of the buzz around Robert Pattinson's Cosmopolis centered around the idea that this was a whole new, and inherently superior side to the young heartthrob. After a career centered around films where he romanced women (The Twilight Saga, Water For Elephants, Bel Ami), he was finally getting respectable with a David Cronenberg film where he was doing more conventionally manly things like shooting guns and engaging in casual sex with nameless hot girls. To push it even further, one could argue that McConaughy was only able to get critical respect after he stopped romancing women and started raping and torturing them. It's the same for actresses as well. Blake Lively starred in Sisterhood of the Traveling Pants, The Private Lives of Pippa Lee, and is now the lead in a long-running television series (Gossip Girl). But the only point in her career when she has been taking seriously is when playing a tarted-up junkie in the male-dominated The Town or the hostage in Oliver Stone's Savages (and even there she was derided because critics missed that her character was supposed to be vapid). Only after Lively played an almost cartoonishly broad 'whore' to Rebecca Hall's 'virgin' did critics say "Huh, she can act!".
The tendency to praise characters who do harm to themselves or others over characters who don't necessarily trade in violence extends to actresses as well. We mock or belittle actresses (Katherine Heigl, Jennifer Aniston, etc.) who appear in romantic comedies (which primarily appeal to female audiences) while holding up the actresses (Jennifer Lawrence, Rooney Mara, etc.) who play action heroines (or appear as token girlfriends in male-centric pictures). And just what exactly made Brave's Merida a better role model for young girls other than the fact that she didn't want to get married and occasionally dabbled in recreational archery? Her character is quite similar to Ariel from The Little Mermaid, yet the world at large thought her to be a superior role model because she knew how to ride a horse and wielded weapons in the marketing materials. The presumption, sight-unseen, that Katniss Everdeen was a better role model than Bella Swan (arguably true) stemmed less from the actual stories they appeared in (since most of the editorials were written before The Hunger Games was released in theaters) but rather because one pursued romance and the other killed in order to survive. It's no secret that we, as a culture, lionize 'warrior' traits, but the extent that we seem to hold fictional characters who pursue love or peace over those who pursue 'adventure' if not outright violence is a little disconcerting when applied to our national mood that demands fabricated machismo from our elected leaders and our would-be heroes.
So now Matthew McConaughy is a 'serious actor' because he plays a character who commits an act of unspeakable sexual violence in a new William Friedkin film (a scene that stops the up-to-that-point terrific Killer Joe dead in its drags in order to revel in the brutality in a black-comic light). Robert Pattinson is now a genuine badass now that he makes films where he wears fancy suits, sleeps with random hotties, and shoots guns in Cosmopolis. And on the other side of the coin, Brave's Merida is automatically a superior character and/or a better role model for young girls than Ariel or Belle because she shoots arrows at trees while riding on horseback. And Kristen Stewart's Snow White is automatically a superior character compared to Bella Swan because she spends five minutes dressed in armor and engaging in open warfare. This is a critical and pundit class that puts characters who do violence or harm on a pedestal over characters who engage in peace. This is a fetishization of fictional violence, not among adolescent boys but among the would-be critical establishment. The actor or actress who plays characters of action shouldn't automatically graded on a higher curve than those playing characters of simple emotion. The end result is simple: we put a higher premium on characters who can kill over characters who can love.