People are proud to show those titles not because they can RP as bloodthirsty psychos, but because they put time and effort into obtaining those titles.
The story written by Blizzard (not Beuargh) never endorses the idea that you are a bloodthirsty psycho. In fact, it frowns upon bloodthirsty psychos. Garrosh is shown as the villain, Sylvanas is shown as the villain, etc. Ion went as far as to call the player character the "Hero", and a hero is not a bloodthirsty psycho. Blizzard never endorsed that. You can put in your TRP3 profile that you are a bloodthirsty cultist of Sargeras, but in Blizzard's story that will never be endorsed as a good quality.
And this is the same company that just removed the word "bitch" from the Cataclysm questline because they deemed it too toxic for children. They will NEVER insinuate that genocide can be good. Warcraft (like every single piece of fiction in the history of humanity) has a message to tell the audience, as it's been the case since forever. They are not going to tell the audience that genocide can be justified. They will never frame Sylvanas as "good" for committing genocide at Teldrassil. They have never framed genocide in a good way, and no story ever has really... for obvious reasons.