How do people who int feed/be toxic every game not get banned? And can they be banned still?

SORRY FOR BAD VIDEO QUALITY, THANKS

Ok i know some of them do, and there isnt a whole lot that do these things but the ones I do see almost never get banned when i report them, by which i mean i dont see the little notification saying that they got punished. I wouldnt be bringing this up because if its a one time thing i dont really care ill just report and move on... however recently this little cuck has decided to be toxic and ruin games for me like 3 times in a couple days (thanks riot matchmaking for putting me with him btw, gotta love em) he just talks trash and ruins the whole mood of the game, even if we win he'd still end up making the game feel like a loss. And this isnt the first time either, i see a lot of people like this but they dont usually get put with me in a game after, but this draven tyler1 wannabe is ruining the game for god knows how many others and he just gets away without so much as a suspension. I guess i just wanted to ask what can be done? Can he still be banned? If the answer is to just hope and pray other people report him then I dont understand i guess. This is my smurf acc and im trying to get to level 30 fast without toxic int feeders like this, feelsbadman :(

Edit Im the zed in this footage.