Sorry I cant agree with you.
"Unskilled" players shouldn't be banned. They should have their own ranking so that they don't get mixed in with thier good and/or mediocre players, but not banned.
The ELO system is supposed to do that. Even mediocre/good players will have a bad game. It sucks, yes but because of the snowball, taking a death early can cause a landslide and make you have a low k/d/r. That doesn't mean they should be banned. Nor if a player truly is horrible, should they be banned. They just need to play with other players around their skill level if they perform at that level consistently.
If you find yourself being grouped up with really unskilled players a lot then it's one of 2 things:
A) The ELO system needs some tweaks that help separate the mediocre/average/good players better.
B) You need to do some self reflection because your already grouped with the terrible player group.
Either way... just banning the vast majority of casual gamers who play the game for fun and don't take it as serious as some isn't the answer. Likewise, abusing a system that's meant to encourage good players by using it as a trolling tool to get a player banned isn't the answer either.. you will just make the dev's change the honor system so that you can't do that anymore either.