"Unfair" CSR Loss still a thing. Why?

By “unfair” I don’t mean that you’re paired with bad team mates.
I mean, when you’re paired with bad team mates, the other team have mics and are using call outs, all your team quits after they all get terrible K/D’s.
Then leave you with a 20 - 47 score.
I stayed in the game…got the game to 23 - 50.
I had a 16 - 14 K/D.
Yet my CSR fell.
YES, I lost.
But really? I was left as a 1 man team again 4 people where at least 2 were using call outs.
This really isn’t fair.
I think if a game becomes a 1 on 4, your CSR shouldn’t fall.
343 have made JIPs in Arena not a thing, so “you don’t lose your hard earned CSR” and what about when people leave a game? What happens to the people who stay in? What happens to their hard-earned CSR?
This isn’t the first time it’s happened, but I am slipping down with my CSR (onyx) due to teammates.
Fix this, for the love of god…