You talk solely about MMORPGs ?
All rpgs... adopt the holy trinity concept (healer, tank, dps)
The same could be said about football or any other team sport.
and end up with 5-10 min boss fights where they follow a predetermined macro they read from a guide. These fights allow 0 player creativity. Same combo spammed every battle, same outcome every battle, they follow a battle chorography like bots. A bot would be more efficient than a human in this case, 0 lag, perfect coordination, 100% ability to dodge aoe effects.
Then I would never see a reason to play this game...
What if battles were luck based. And chance to win was based purely on luck.