It has a lot to do with the fact that the archetype of the rogue/assassin has shifted from its original concept.

A rogue used to mean someone like Garrett, who avoids confrontation as much as possible and uses his dagger only to eliminate obstacles quietly. Today, when you hear the word rogue, it is often thrown around to refer to these ninja warriors that can go toe to toe with actual soldiers and even spellcasters.

Personally, I blame WoW for this.