I think it's rare most people get paired with GENUINELY incompetent players past rank 2300. Loosing games now is either down to bad picks, poor communication or just getting outplayed by teams that are just more on form.
People seem to think they're a hell of a lot better then they are. Not just that, but they think they're good ALL the time leading to this weird sense of entitlement in the ranking system. If you've been hovering around the same rank for a week purely solo queing, that's probably where you should be and the system is working. Not everyone can be Diamond+. Most of us have to be fodder for the better players.