Blimey that'd be some time invested. I think I put in around 700 - 800hrs into KZ2 (multiplayer) and probably the same into COD4 (or MW1)... but that is off the top of my head. They're probably the two games on top of my list.
Grinding is what makes mmo's so I doubt it, to be fair if they didn't introduce an update where you had to grind for mats to charge your armour I probably would have kept playing but it was poorly designed and pushed the grind over the top. Skyforge feels less grindy but it is still there so we'll see how many hours it gets but I'm guessing a lot less.