I don't know what to make of it, especially since you're at a higher tier than me. I'm in Bronze IV, and I CONSTANTLY have to struggle and fight against my own teams. You can't give anyone constructive feedback (e.g. "hey man just sit at tower until lane phase just don't die and we can win this), if someone loses lane they are at risk to just rage or afk, and nobody takes responsibility for their own mistakes. It seems like nobody is out to get better. It just seems like everyone thinks they are already pro material, but everyone else is simply holding them down. While I can understand why it would appear that way, I've been on both sides of the coin too many times to count. I would say everyone has the same statistical chances of getting paired up with impossibly negative players, but that would just be intellectual dishonesty.
My thoughts: If people boast how unafraid they are of the justice system in League, then the justice system isn't working. If people are not afraid of getting banned - it means it doesn't happen often enough. Just something I will let float around out there for a bit.
And also, I'll agree with you on a point you brought up: Why do we have to suffer because of negative players? How come there isn't a "Loss prevention" system for teams who experience an afker, or similar behavior? Sure, I get that Riot doesn't want to give a reason to encourage that behavior. Riot wants people to understand that they are hurting their teams when they do this and that should be the main deterrent. The problem is, at least in my skill level, nobody cares. Nobody cares about their team, everyone is in it for themselves. If they can't carry the game 30/0/0 and win, they want no part in it.
Those are my thoughts on the issue. But I'm also incredibly frustrated because this is something I struggle with on a daily basis.