I disagree with you there, Head , Cummins, even Marsh play all formats. When you have player who is good enough to play all three formats and willing to play, denying those players a chance to play all formats is wrong.
To me you need more multiformat players or you will be left with guys like Pujara who will kill Test cricket.We are already seeing how Impact player rule is wreaking havoc. You need multi skilled and multiformat players.They bring exictement to viewers .
I am not defending BCCI here but it has done nothing majorly wrong in my opinion other than fighting for favorable scheduling for the team.It has been giving time to all local tournaments.Its teams have been at the top of rankings and getting to knockout in all formats.The only thing they have not done is win the trophies.It is more on players than BCCI.
Sooner or later things will turn.Trophies will come.It took Australia 2021 to win t20 title.They had lot better t20 players than the team which won the title in past.
Scheduling is where BCCI need to put their foot down and give its team fair chances, ECB are crooks, they have always looked after their own interests.