Difficulty of normal content.

[Bryson]

I would say 10 years of msq does a more than adequate job training players for them

If this were true, someone like OP wouldn't exist. The mere fact that OP unironically doesn't even want to queue for normal m3 and m4 because it's "too had for casuals" is proof that MSQ doesn't sufficiently teach people how to play game. I'll admit where one draws their "knows how to play the game" line is subjective, I still think getting to max level and people being lost like OP, doesn't make the MSQ teaches you how to play the game, all that compelling of an argument imo