Compared to David, Bernardo's still a bit lacking in the passing game. His decision making, short game, and creativity aren't at David's level. He's not lacking in these in anyway, it's just David (and KDB) sets the bar real high. The fact a guy like Gundogan gets called not good enough by some on these boards is testament to David's and KDB's creative and passing qualities. So Bernardo's got some work to do.
The good news, is that with time, hard work, and the right coaching; all on the plate for Bernardo; he should eventually hit that kind of passing game. It might take a couple of years to make the transition but there'd be plenty more years afterwards to enjoy the transformation.
The slightly bad news, is that I think there will be certain elements that Bernardo will never take up of David's. Such as his incredible ability to drift between lines for one. That feels almost unique to him.
The particularly good news is that there are some things he can do that David can't do, that give him an arguably higher ceiling. For one, his dribbling ability on his left is phenomenal. He's a very athletic player, with a great ability to cross and shoot too. So if he can develop the passing game David has, or close enough to, we should have on our hands a ridiculously good footballer.
Good thing he didn't sign for United I guess last year.