I'd say it is partially what you mentioned about it not being accepted, but in reality it is a matter of commitment more than anything. These spoiled and coddled NA kids get to move into a nice big house, have all of their stuff paid for, and in plenty of cases we have seen (from it being shown publicly) their isn't a very strict environment from coaches and management.
In Korea, for example, they are barely sharing spaces bigger than a 1-2 room apartment sometimes during the times they are "in season" playing. They have strict diets, are required to go to the gym in some cases with each other, aren't allowed to have girlfriends or at least have them around, unlike most NA teams. They don't just play a few scrims and call it a day, they grind their asses off, and in most cases for less money and terrible streaming deals (thanks to how the payouts and management works there).
They want to WIN where in NA it is just something kids think is cool to do and get paid for. How many kids wanted to grow up and get paid for playing games, sitting in their bedroom playing Zelda or something? In Korea they do it because they are good at it and want to win. In NA in most cases they do it because it is a pay check and fun. It is hard work, and we've seen plenty of cases where the pro players aren't willing to put in that hard work. Look at Cop from Curse/Gravity. Dude didn't play but maybe 5 solo queue games in what, 2-3 years? Imagine how good Cop would have been had he actually practiced and put in effort, seeing as he was still statistically relevant with little solo practice.
Most of the problems are easily fixable with more dedication, but that isn't going to happen, because it has to start first with the owners, and outside of, I'd say 2 and a half of them (Steve from Liquid, Regi from Tsm, and at one point HotShot, who apparently hates League right now so he declared) really care, so not holding my breath of NA winning more than unimportant tournaments or events at best.