The best receiver of a ball that we have, keeps possession under heavy pressing, often makes the difference that wins us game and has balls of steel / always willing to step up.
Pep picks him for the biggest games for a reason.
PS. And the ‘not getting involved’ thing, that he sometimes gets called out on, is him sticking to his role by keeping high and wide like Pep tells him to, and that actually is being involved as it keeps the opposition defence stretched wide and makes space for our overloads down our left.