Hameed needs time to develop and patience. He is not a modern style player in fact he is a bit of a throwback to the old days.
People commenting on here don’t look back to recent history of the development of young players in the long format of the game.
Cook and and Bell around 21-23 when they played test cricket, Ollie Pope more recently but he is middle order.Apart from those 3 most of our test players get selected a bit later.Whether that is right or wrong that’s how it tends to be...maybe because it takes more time in our conditions.
We are not India or Pakistan where they get younger players in far younger, it works for them but it’s not common over here.
I personally think Hameed has all the talent and temperament to make a very good test player, maybe he needs a move away from Old Trafford and a coach who can work with him better,and perhaps needs to find the drive to improve himself as well.