I have to disagree with your conclusion though, mainly based on historical arguments. The Look Inside dominance is something that has not been there for an extremely long time.
When R&G was the preferred tactic back in season 12 I bought 3 talented 18 year olds to train.
Back then, the elastic effect wasn't known yet, but the salary formula had been pretty much figured out and salary calculators started to appear.
I pondered a lot on how to train my players and what kind of team I wanted to build and came to the conclusion that the best way is to play look inside, because it's the most salary efficient way.
Of course, many more people came to that same conclusion and started training their players accordingly.
So, my theory is that as soon as the salary formula was figured out and managers could calculate which is the most efficient way to build a team, more and more managers started to train "look inside players".
Now that these players are all fully trained, we're seeing the look inside dominance in full effect.
You're right, the training and salary system didn't change. What changed was that managers figured them out and adjusted the way they played the game.