Part of what you're sharing does seem to support the theory that high JR is not the solution to making a high percentage of 3's.
It does, and given the cost/value of JR I do think the salary formula needs to be adjusted.
But, there's nothing I see that indicates that an outside team can't have success at the top levels of the game with the GE and salary formula intact, it's just that few have the inclination or resources to do so, and the current pool of players doesn't support it. It's easier to get a guard with 16 IS than a big with 16 SB.
That said, my outside rotation last year, with a trio of well-rounded 7/19/19/19 bigs would still cost less than Dionysus' team. With a trio of bigs that had 16, 10, and 9 ID, I still made it to the knockout round of B3, losing to Dionysus by 22. His closest win was the championship game, by a margin of 12.