Do people actually think that their toxicity doesn't cause them to lose more games?

If someone is in a game and starts acting toxic, do they really expect to not make others pissed also and lose the game due to the toxicity? How do they even continue to climb ranked when they are acting in this manner? How does Riot let this stuff happen? It hurts the rest of the people who try to stay positive or even just ignore it.

I normally try to ignore toxicity, but it seems like every single game that both teams have one or more extremely toxic people on it. This is the reason that the League community is considered so terrible. Riot should bring back the tribunal system and elongate bans for toxic people. It's only through strict punishment that people may learn that acting like a kid, throwing a tantrum if something doesn't go their way, is not acceptable.