I have seen many responses each time breaking down why the ranking system correctly adjusted the csr of any given player complaining about it. Obviously since the system is not actually bugging, the response is always going to be "it worked like it was supposed to" "you are ranked where you should be". The real problem is that the model that has been created might not be actually good. I am aware that creating a good ranking system is not easy but I think it would be better to take people's comments and criticisms into consideration rather than just brushing them off and saying that system worked as intended.
Here's an example of a game in which I played where I believe a better ranking system would not have ranked me down so harshly.
The other team had a player quit relatively early and we went on to lose the 4 v 3. We lost almost entirely because a player on my team went 3 and 16 (another went 8 and 16). I played very well going 20 and 6 and I wasn't trying to nurse a KD I was actively trying to help my teammates and win the game. I lost more than half a rank from this loss. Now I don't want an explanation about how the system did what it was supposed to in that situation because I'm sure it did. What I am saying is that I believe the model currently being used is lacking information and accuracy because it really makes no sense for someone to rank down in that situation. There's nothing I can do to stop my teammates just running in and getting themselves killed.
Losing a 4v3 will always have a slightly weird outcome because it's extraordinarily rare. But it would overcomplicate the model if we added every possible exception to it, and make it worse overall. We don't add things to the model that almost never happen because it makes things worse overall.
99.99999999999% of the time, players exactly like those on your team win that exact same type of matchup, so when you lose it, the system makes the logical assumption that people on your team aren't as good as it thought they were.
That said, you need to separate out what the visible system can do (CSR) and what the backend system models about you (MMR).
The visible system has no idea how well you played that match, so can only guess based on the win / loss outcome what to do, and 99.9999999% of the time, the correct thing to do is exactly what it did. So you lost 30 CSR.
The backend model (MMR), on the other hand, saw how well you did (kills) and did not dock your MMR as much as it did the other players on your team. For example, the 3-16 player lost an equivalent of 87 MMR from that match.
You, on the other hand, finished that match with an MMR still higher than your CSR, so, yes, when stuff like that happens, yes, you will lose a lot of CSR because the CSR system doesn't look at kills. But you will gain it back quickly in future wins because the system overall goes towards your MMR.
Also, as far as accuracy goes, the best judgement of a skill system is how often the higher MMR team wins the match, which with this system, is the highest I've ever seen. Bending over backward to add exceptions like this to the model would lower that accuracy. So better to deal with the occasional exception and move on.