Actually, they are sorted by themselves somewhere beyond 1k rank.
No, there's been plenty documentation in MOBAs, which often has a similar system of "rank." Often called the "trench," you can't escape it by going through it. Games are not determined by skill, but by whose teammate rage quits first. Over enough games, it evens out to 50/50 and you can neither rise nor fall beyond a modest range.
In 1v1, this archaic system of "let the gods decide" works okay. 2v2 and above muddles the 80% curve of players, deciding their fate via the law of averages or they manage to be blessed/cursed in an anomaly. As with any large system of numbers, patterns do occur, such as players escaping the trench or skilled players falling to the bottom of the trench from a long series of quitters on their team. The olympian players and the clueless will not see a problem as they are not our average player. Those stuck in the trench will be unhappy while those that barely got out of it via skill + luck or, more often imho, mostly luck, will try to keep a lid on the system to maintain their benefit.
And, let's be honest, the AI is a death sentence. The enemy immediately pushes that side and capitalizes on their advantage. Now, in theory, a pro player might handle a 2v3. But this supposes that the other player on the pro's team is "onboard" and capable. But, true to human nature even as far back as the first shield formations, weak players will tend to hide in the shadow of the better player, collapsing a theoretical equal-push from the 2 players. Somebody like Helping Hans will lose in large matches as his fan/random teammates collapse and leave him to take massive losses.