Stats being more or less effective on certain champions when you buy items

Phreak brought up a really cool idea in his recent patch notes talking about ornn's new passive where he gets 10% more armor and magic resist from items. He mentioned how it would be a really cool way to make tanks in general more effective if they gained more stats from tank items as a entire class.

Made me think it'd be a cool thing to do with every class perhaps. Like maybe adcs get more attack speed from attack speed items, or supports get more mana regen, mages get more AP, bruisers get more AD, assassins get more movement speed and AD, AD casters like jayce/ezreal get more cooldown reduction...

idk i think it sounds cool on paper. could feel like garbage in game.

Could also just turn the game into smite where it's actually impossible to buy ad items on mages or ap items on marksman. That could be a different discussion but I feel like it's close enough to the question phreak brought up here.

Should certain items be more effective on the champs that it works with? Or strait up impossible to get on champs it is bad on? That'd sure stop the is it meta people from trying 3 recurve bow soraka jungle.