I don't expect the majority of even high level players to have any fucking clue as to what they're doing.
People just don't care enough to learn how things work. It wouldn't matter even if they did because the best rewards are accessible to the lowest common denominator.
Soooo much this. It's astounding to see that 80 percent of people twice or more than my level are doing half my potential damage.
As for the whole soloing contents issue, we need to consider two things. A new player cannot recreate what happened with Oberynn. A new character, yes, but not new player. The other thing is money back up.