Marchisio is key because he is smart good DM that organises the midfield. But the reason he is key is not just quality but the fact our squad is flawed, we had no one that could play his role well when unavailable. While Dybala is part of a well covered attack but he has still been HUGE for us, more then others, scored vs against all big opponents, saved us on weekly basis for months, scored 20 goals and 9 assists, thats ridicolous impact for a debutant in the big leagues. A quality DM isnt more of an MVP just because we are flawed in holding mid depth.
FFS it should be dead clear the best outfield player was Dybala, then comes Pogba with ridicolous 10 goals and 11 assists while doing tons of work in overall carrying us 2nd half of the season.
Dont take this as a diss for Marchisio, I used to watch frigging Azzurrini and Empoli games regurarly for him. But being important quality player for us doesnt mean he is our best player for the season. Thats what MVP is.