Imo, Corrupted gear is a better system, because it also comes with heavy downsides. Sure, that 415 bracer you got from a WQ is better then the 445 that you ALSO got from a WQ - But with the previous system, that 415 woulda just titanforged to a 460 or whatever. Same result, you just had higher ilvl with the previous iteration.
With corruption, it has obvious downsides. Sure, at lower corruption lvls they aren't much of one - But I had an alt that had extreme corruption "luck", and trust me - At 250 corruption, you die as soon as you take damage. So instead of getting EVERY piece with Titanforging, you just want a few pieces with corruption. Sure, you got that 415 crit bracer now, but it's week 2 - You'll get a 460 ilvl crit corruption, idk, belt, and because you don't want your corruption high, you can get rid of that 415 piece with crit corruption and get 445 bracers with crit rating (Or, hopefully, 460-475 bracers with crit rating)