i'm glad you put greb and saddler in your comment. they are two of the dirtiest, but best, fighters of all time. It also depends on your era. **** that Greb did would get him DQd in about 14 seconds this day and time but back then, it was part of the game. So to answer no, it's all contextual.
It shouldn't really, unless said fighter was just a blatant cheater who only got by with spoiling and roughing tactics. The fighters you mentioned were definitely dirty, but they were able to get by with what they did due to their experience, guile, and ring intelligence. They were the epitome of the seasoned, crafty veteran. Not just unskilled spoilers.
I agree. Spoiling and dirty fighting IS a part of the game. Just depends on how you use it. Duran was an artist in dirty tactics against Davey Moore.