Rainbow 6: Siege has been making massive strides in the realm of reducing community toxicity. The player reputation system lets players report toxic players, griefers, and cheaters which lowers their reputation. At the end of each match, players can commend their teammates (and the entire other team) for specific positive characteristics. Players with low reputations get sanctions, and players with high reputations receive bonuses that increase chances for in-game rewards, and occasionally receive thank-you gifts for being positive influences in the community, like alpha packs (loot crates). It’s a solid system and I immediately noticed not just a decrease in toxicity but an increase in positivity when these systems were implemented.

In theory, you could start match people with low reputations together, and people with high reputations together.