Stop spouting nonsense. No wonder you're getting downvoted. Here's a sizable list of what he lost when he was reworked:
-0.31 Base Attack Speed
-15% Armor reduction on Passive
-20+ HP healing at early levels
-5% to -35% AD bonus damage every third hit depending on whether you used to max Q or W first
-120 base damage on Q
20% total AD > 40% bonus AD on Q
-0.25 second knock-up duration on Q
-80 base damage on E
-0.75 second stun on R
-25 Armor per enemy hit by R
-25 MR per enemy hit by R
There were plenty of things they nerfed on Xin Zhao when he was reworked. He objectively does less overall damage per rotation for the entirety of the game, far less healing in the early game, and has much slower early clear speeds. In return, they gave him a lot of utility he was sorely lacking with a ranged skillshot poke ability and a 3-second block against ranged damage.