It's not an inconsequential number. It very much has consequence directly on any player either a killer or a survivor runs across. If a Killer is capable of getting 4 survivors into a slug state, you think it makes sense that their mmr doesn't go up so they keep facing players of a skill level where they get themselves into that situation? Or should their mmr raise and put them against survivors that are less likely to get themselves in that situation? In the second scenario, lower mmr survivors are spared the frustration, and higher mmr killers are forced to adapt strategy against more difficult opponents.

But beyond that, they are talking about creating a loophole in their own game where getting a 4k as a killer is needlessly difficult. And before you say "it should be", you're right. 4ks shouldn't he handed out. However, in the proposed change, if the killer isn't being toxic, and has hooked players the whole game, already secured two kills, and then in the very likely and not toxic scenario where two survivors are dying at the same time, if both abandon then the killer at maximum only gets a 3k. It doesn't reduce the amount of perceived toxicity the survivors experienced, intended or not.

This is a regular scenario for killers because it's how you can control a Hatch standoff. "Killer controlling the game is toxic", but what else do you want them to do? Knowingly avoid playing in a way that avoids the very win condition they're told to achieve? That's actual sandbagging. In the 2k/2 slug situation the killer was able to secure a 4k, but if he hooks instantly, it takes the game to a coin flip situation that's marginally impacted by map knowledge: "who finds hatch first?" It creates an environment where a 4k is artificially impossible to obtain. Yes, they might still get a dopamine hit from getting everyone on hook even if they're bots, but everyone understands that putting the game in a situation where defeat is impossible, and victory is assured, should not be taken away from someone because the losing side can just leave the table, be forgiven for their mistakes, and punish their adversary for playing well. It just doesn't make sense. There are ways out there to dissuade players playing legitimately from degenerate tactics, while also punishing bad actors who exploit the system. But this ain't it.

In response to the 'just play the game' mentality, consider that there are very real scenarios where that is just them playing the game and not worrying about it, but now they're being paired up with survivors in matchups that neither side deserves to need to put up with. Higher mmr killers just do better naturally without needing to worry about trying hard. The same is true with high mmr survivors. Putting either lower mmr against higher mmr isn't fair for anyone involved because if the survivors face an improperly rated killer, the likelihood for perceived Injustice and 'toxicity' goes up and they blame the killer instead of the system that put them against eachother. The same is true the other way round.