Yes, because playing everyone removes every random element of the game.
Would be curious to see if you would be so adamant of that had City won QPR with a couple of gifted penalties or playing against their reserves because of some random cup final. It looked strange enough with QPR hoofing the ball from kick-off after 2-2, something I never saw in a football pitch (I'd expect them at least to make a couple of back-passes and receive some pressure before doing that).
And that's from someone who cherished the moment, just for the small sadistic pleasure of witnessing a meltdown here.
I maintain that unless you have a strict policy of objectiveness that the winner of each individual game was the best team in that game (because they scored more), it's a ridiculous logic leap to just accept that the best team always win the league. Probably more often than not that is the case, and it certainly has a lot less variance than cup competitions, but when they're won by small margins, there's obviously room for debate.