I am not sure about this. Nowadays, the coach has become a nominal role within the Indian team. Previously it was not so. Damaadji (the coach) manages to hold on to his job by keeping the captain happy. I don't think that he has any other contribution to the team. Kohli doesn't prefer anyone else as the coach, as he don't want to listen to others and undergo rigorous training routines. Perhaps India is the only team which doesn't have a real coach.
So you think that Ravi Shastri is not a good coach and Virat Kohli is not undergoing rigorous training routines, check out historically and i would say this Indian team is the fittest and each and every member spends a lot of time in the gym working out and it is evident in their performance.
Team India is having the best players and the bench strength is really good and historically we never had these talents in abundance.
Yes, this is the fittest team and one of the best team in the world as well but they are exposed too much in my opinion which caused lot of injuries in the recent weeks and months for the main players it is also a concern right?
In general, Ravi Shashtri performed poorly as a coach even among the cricket community but all he is doing is trying to influence the captain and his decisions.