Back then everyone worked hard to be good, and in order to hit the top of the leaderboard you had to become an all rounder, or at least an average player in every scheme.
Nowadays people want to make the league suitable for them to play only their favorite schemes because they are too lazy to learn all the others, yet they want changes to be embraced as competitives players, this doesn't seems right and fair to me, actually it drives me crazy. The idea of individual leagues for every scheme were good too but we are probably way past the point here just like your idea, we are too late for changes.