I'm going to give Gavi a pass because he's still 18 or 19. And Pedri a slight pass for now, as he's dealing with Busquets at DM.
But if Pedri continues to not dominate midfield (versus good teams) say by the end of the 2023-2024 season, it's very alarming.
The problem is with these age related arguments is that players these days are hitting their ceiling and peaking faster than ever before, especially ones who were starters from a very young age.
Most professional players by the age of 18 or 19 have already peaked in technical ability, they've been doing that for over a decade at that point almost daily. There's not much more you can learn in terms of basic technique.
Then the only things you learn after that are mental/game experience based... Most youth players of their ages will not have played much pro football, so they have a lot to learn, but these two have a unique situation. With how many pro games Pedri and Gavi have played already, there will come a point soon where they can't learn much more as they have already played so much football at young ages.
Probably Pedri and Gavi won't improve that much in the next years, especially Pedri who's ability has been quite consistent in the last couple years.