T20 ruines player skills
Pakistani players don't have the supreme academies like in England or Australia or New Zeland
Majority of players come into Senior squads after playing tape cricket and slog fest Tournaments where the Tennis cricket bat shot is best way to hit a ball.
In past we used to be able to train few players privately after they were discovered on basic skill improvements and that used to work , mix of street cricket and little bit of training
But when you put T20 into Mix , the players are completely at loss over how to approach the Longer formats of game
Every shot has to be a hit , there is no focus on placement or taking 2's and 3's to keep scoring moving. Unfortunately that is the problem we have and it will not go away anytime soon provided we play and Emphasis T20
One other thing to note , that in Past we used to play 3-4 Month long test /ODI series together with lot of regional friendlies and that used to serve as a Training and On the job learning for many raw players.
The game has evolved too much, street cricket can only get you so far