The big blond, blue eyed, bad guy is a common figure in movies today. He is usually the right hand man of the main villain.
I would say that before DL, blond hair and blue eyes automatically meant good guy, and that he was the first to really brake that mold.
You could argue that Rutger Hauer made it big in Blade Runner with a similar look before DL, but that´s not excactly true. Hauer had white hair and light blue eyes and came across as very unnatural looking (for good reason), he was kinda stocky and didn´t have the classic movie good looks. Dolph was the first sterotypically "hero looking actor" to be a bad guy. Now you see it all the time.