Nerf Zhonya's. Buff Zed

I don't know why people assume that Zed is good or op. Why does he do no damage to a squishy ap champion that only has Zhonya's? I played a game where I had 25 kills and full build. These ap champions and adc on their team got 1 shot so easily at the start of the game. As the game went on, I got more fed. After the ap champions got Zhonya's, I dealt absolutely NO damage to them. I had Lord Dominik's and still did no damage to any of them. The worst part was, these ap champs that weren't even that fed, 1 shot me instead. Why does Zhonya's have to negate half the damage that Ad champs deal? Zed is only op when he is fed, and yet he still deals no damage because of 1 single item. Please get rid of this garbage or at least nerf it. In addition, Maw, Mercurials, and Merc treads don't negate ap damage whatsoever. Please buff magic resist items rather than armor items.