Saying that Matt & Jared won because of the roles they played is kind of misguided. It sure didn't hurt in the grand scheme of things, but come on, Chiwetel plays a guy who is turned into a slave, Leo a master manipulator & degenerate, etc, etc, because these are the roles that are literally Oscar worthy, that"s what it takes.
Now, saying one performance is better than another when you got Leo, Chiwetel, Dern & Matt & Christian all doing fantastic work, it's silly. However, I doubt that Matt gets the Oscar solely for DBC, it's a culmination of his incredible comeback + True Detective probably helped him to win as well, it's not like it's a surprise or anything, he got ALL the awards that mattered prior to the Oscars (aside from BAFTAS where he wasn't nominated for some reason).
Matt was incredible, but I think what's being judged as well are the roles, how can you say OBJECTIVELY that one guy was better than the other when they don't even play the same roles, or one might have a showier role than the other.
Matt won, it's completely deserved & legitimate, end of story.