The Stubborn "Unskilled player"

Playing with someone that's struggling to get a grasp of the game's mechanics, or a champions mechanics doesn't bother me. But the type of player(s) that really grind my gears are the ones that consistently play, have horrible losing records, and don't understand/want to understand basic concepts of the game because they can't take a a single drop of constructive criticism. Instead they believe their style of play is perfect and that anyone who says otherwise is an a**hole, idiot, mean, etc. League of Legends is a team game - which means you have to be willing to listen to your teamates(within reason of course). This game may be played online it but team dynamics still apply like any other sport. It is really demoralizing to be dealing with players that are so stubborn they end up making the team atmosphere super toxic which leads to arguments, flaming, reporting, etc. If people really can't understand how to take a little of bit of friendly advice or criticism how can you grow and get better? Players like these are sometimes even worse to deal with than the feeders/griefers. When your match history clearly shows you're not a consistent empowerment to your teams, you can't blame it all on everyone else. I don't believe that the "Unskilled player" report was appropriate, but I feel like there has to be a better way of giving some type of disciplinary punishment for stubborn, easily triggered, know-it-all players. What are your thoughts fellow Summoners?