It's easy to blame SE for how poor the game's support structure is for learning but when you are playing an MMO, you should expect to do your homework outside of the game or be social inside the game if you want to be good. It's as easy as seeing players in A12S gear and pming them for advice or finding / starting a relevant FC / LS for self improvement. With how bad a lot of players are, it's not simply an issue of not having the tools. It's about overall aptitude, engagement, and motivation. At this point in time, you basically have all the information on everything already out there. If people don't want to do the work to improve currently, that's not evidence that they will want to do the work even if SE improves the in-game tools. As long as SE doesn't just abandon the lower spectrum of their player-base (and in making adjustments to rotations / skills, SE clearly isn't), you're going to have players that just don't want to do the work or might not have the aptitude to excel even with the work. At the end of the day, what SE sees is their internal clear-rate data and we are all in the same pool in that data.
The players who are at the top are playing the same game as the ones at the bottom.
Like I said earlier, one of the core issues is the gap between players who can get the most out of what they're given and the ones that can't. SE clearly wants to close that gap by making it easier to get the most out of what you're given.
That's just not true. If every job could do 2000 DPS by pressing 1 button, then a lot more people would clear hard content. If every tank had on demand hallowed ground for every tank buster, then a lot more people would clear hard content. If healers had a surplus of infinite range instant AoE healing / shielding, then a lot more people would clear hard content.
Yea, the mindset is obviously also important. But, how hard or easy the game is to play also obviously has an impact on clear rates.