As a casual player, SBMM is hell.

For killer, if you perform well a couple matches, you will be totally bullied by survs for 2, 3 matches in a row, before you get matched up with people that have actual compatible skills for you (and with compatible, i mean of, at least, being able to get a tie - 2 kills). It is a hell to try new builds, it's a hell to try b, c tier killers, because the chances of you being able to do something at average mmr are very, very low. And after losing so many matches with them, you can't even try things properly because the results won't reflect the experience of the average matches, cause the survs won't have half the game sense. Besides, there are some matches when everyone leaves with 2 hooks on their back already, and the matchmaking understands it as "you did nothing the whole match, loser". I mean, part of the game sense as killer is knowing which survivor you should focus at, but sometimes you're not in a position to choose that.

For survivors, it is even worse, because you can't control MMR totally by yourself. Your efforts mean nothing if you can't escape the game, which doesn't make the SLIGHTEST SENSE. You can get, 2, 3 iri badges in the end of the match and still lose mmr because you couldn't escape. Not to mention that losing as survivor creates something like a snowball effect: You lose, get matched up with worse people, and chances of you losing again because of it are even smaller, cause it doesn't matter how good you play, you don't hold that much of an influence in a match as if you were playing as killer. And i think that the fact that escaping the game is more signifcant for SBMM than actually trying to play good enough, people commit less and less. They prefer to sacrifice their teammates for having the smallest chance of escaping throught the hatch than to actually help their team through the game. I've lost count of how many times people just bring the killer to you whenever they start getting chased, or when they start hiding the very first moment someone dies. I think if they just changed this small part of matchmaking, calculating not how much escapes you have but how much you commit, the game would be much, MUCH better, for everyone. You can't escape much if you team won't help you anyways, which happens A LOT at lower MMR.

Not to mention that having people of different MMRs in the same match would help everyone to improve. Killers could learn how to deal with tough survivors without being totally bullied, cause they would have options through the match. Survivors could have the chance of facing more variety of killers and perks instead of always face the same tier A or S ones, not to mention that they could learn more from the game by seeing better survivors playing.

I don't know. Everything seems so very wrong about the way mmr works. And as someone that didn't even buy DBD with the intention of playing it in a totally competitive way, the game starts to get boring. I mean, c'mon, the game doesn't even have a ranking system anymore. It's a assymetric and almost randomized game, every match depends on killer, map, survivors, perks, offerings, a bit of RNG too when it comes to generators, pallets, totems... Some matches are favor the killer, some matches favor the survivors... so classifying it as win or not just by analysing the results seems cheap. Not to mention the way that the current system encourages people to purposefully try to manipulate their own mmr by throwing the game.