I play lol and i know you can get banned for smurfing. And hearthstone you cant smurf? its literally impossible. You arent carrying anybody. You would have to pay for packs to even make a decent deck.
Yeah they should it only takes i think 15 hours on average to reach lvl 25. League of legends takes days of straight playing to get to lvl 30.
Theres a lot more smurfs than people seem to think. If you watch a masters game. (NOT A GRANDMASTER GAME) you can see how many smurfs. Even diamond was awful for it. Also when it reaches the end of the season (last two weeks) I straight up stop playing the game because of how the smurfs start throwing games.