Games, particularly RPGs are about optimizing characters and builds. Especially Diablo/ARPGs. The campaign was never the meat of the game. It's a part of it, but not the core. You can't actually participate in the core gameplay loop without spending decades in game or spending tens to hundreds of thousands of dollars. Actually in the case of Immortal some things are simply not possible by only playing.

That's not a game anymore, it's a skinner box.