This is basically just free gold for the winning team. It doesn't serve its intended purpose unless both teams are roughly even, which is never the case.
I just had a game where I was completely hard countered as Qiyana vs. Kled. I can't do anything in this lane. I can't even farm under my turret, because being hit by a point blank bear trap will dumpster about 40% of my health any time I try to CS, and it gives him vision, so I can't counter it by holding brush.
The only thing I can do to have any impact in this game is roam. But even if I do that, I still lose thanks to plating. My opponent can just sit in the lane and acquire 2-3 kills worth of gold each time I roam. If I stay in lane, he still gets the plating, but more slowly.
This mechanic needs to go.