Ornns armor????

Was looking at some armor scalings noticed something i found completely stupid.... ornn armor at lv 18= 75 lulu armor at lv 18 =81(about average) rammus armor at 18=104(highest) gnar armor lv 18= 65(essentially the lowest) only 2 "true tanks" are lower sion armor at 18 = 74 sejuani at 18 = 73 (at lv 1 sion and morde have lower armor, other than them its mostly mages)

i mean, at his current state hes not bad off, but why was this not addressed early on when he was in his ~30% win rate period?