The punishment system does less than it's ever done before

Toxic groups have completely ruined this community, at least as in regards to normal draft matchmaking. As a solo player, the current patch has me getting matched with toxic groups of 2-4 in more than 90 percent of my games. And it's the worst kind of toxicity: losing on purpose. I've been trying to pass it off as just a bad day but it's been more than a few days now with no end in sight. I'll go play Dota 2 a game I haven't practiced and get an easy approximate 50 percent win rate instead of stay with playing LoL, a game I've been practicing and have learned a lot about, at a 5 percent win rate. The matchmaking is more rigged than ever and it's really a wonder why Riot is doing this. They're still giving me keys, so it's not due to being low honor like what can happen in Dota 2 with its behavior based matchmaking system. Something else is amiss here, something they are keeping secret from us.