It's a great trait if offensive players can track back and help defensively. Most of them dont have enough energy and save themselves for when it matters, in attacking phase of the game, running behind defenders, beating offside trap, counter attacks, etc... Mario isnt your typical goalacorer, 20-25 league goals per year, so without this trait I doubt he would play at top level for so many years. If I could choose, I prefer prolific goalscorer instead and all defensive effort in the game falls flat when you at times make 0 impact upfront, so I can understand critique of him in some games.

But he is clutch af this season so we can turn a blind eye.
Dybala is playing different position this season, so those numbers are expected and means hes addapting well. I like him in this new role.