Dynamic queue doesn't measure how good you are as a team either.
I've already gone through why dynamic queue cannot measure an individual achievement.
But nobody has seemed to think about how it cannot measure team achievement either.
Nobody knows how good your team is in dynamic queue because you might not be going against equal teams. The only way to know how good your team actually is, is to play in organized 5v5 ranked or tournament.
Otherwise, who is to say that your trio winning is because of your special synergy as a trio, rather than just stomping solos? There is no way to measure how good your trio is unless they locked trios with duos.
Even if you were going against other teams of even premade numbers, as long as you aren't a 5-stack ranked team the position of the solos, dictated by RNG, can vastly influence the outcome of the game.
Nobody can measure how good a 4-stack is because depending on the position of the solo it is vastly different every time. A solo in bot lane, for instance, would destroy the synergy that an ADC/support have while an equal 4-stack with a solo in top lane wouldn't be as disruptive to a team's synergy. Sure, you can camp the solo, but you won't immediately know he's the solo while the communication advantages of a voice comm bot lane start showing before minions even spawn. Should team 2 win over team 1 for having the solo randomly assigned somewhere less communication reliant?
If dynamic queue cannot measure solo skill AND it cannot measure team skill, then what is it measuring? After all, "ranked" implies measuring some sort of skill distribution, so what is it?