People are trolling if they play new champions in ranked

People who play a new champ in ranked fail to play him right 90% of the time. They either don't know how to play him, haven't learned to play him well or just first timers who decided to try him out in ranked.

In my last promos, I've had a Pyke build Titanic and Black Cleaver with no lethality items. He kept dying everytime he tried to kill someone simply because he couldn't.

And I don't want to ban Pyke every game because there are also champions that I actually want to ban, my counters for example.

Riot should do something about this, like make new champs unavailable in a ranked for a week or so, or make it so you can't play a champ in ranked unless you've played them a number of times in normals first.