Caught an obvious elo booster

Caught an obvious booster in my last ranked game. I'm getting really tired of trying to rank up by playing master/challenger elo boosters. The account in question is clearly a support main with soraka sona and lulu as their 3 most played champs, and pretty bad KDA with over 10 deaths on a lot of games but if you look at his recent match history the player somehow is a master at fizz and rushes mejais every game with a 32/0/something game. Obviously not the same person playing on the account. Not to mention their shit support games are in silver 4. If you can't manage to die less than 10 times as support (the one who people don't even focus) then you're not gonna convince me you're comfortable enough to rush mejais and go 32/0 in a game as a mid laner (especially when its deadly obvious you're a support main" I'm really annoyed Riot doesn't ban players for this type of stuff because ranked is becoming a "which team was lucky enough to get the elo booster on their team". I called them out for boosting as well and they blocked me. It's just too fucking obvious and really frustrating that to get out of silver I have to prove I'm better than diamond+ players. That's not how ranked is supposed to work.