Still debatable what's his "BEST" position:
LW -> has produced most from this position and became regular starter while playing there
False 9 -> some good games, but in overall very unstable and less productive
RW -> Pep uses him as a RW not that much, but in some big games he has made match-winning performances. Today and against Liverpool at Anfield in 2020 / 2021 season, but as I understand Pep prefers not to use him as a RW
LCM -> CL final and it was a big mistake from Pep, should have had more experience before playing there
RCM -> Still hasn't played there and I think it can be his best position..
In overall, Phil is fully read for midfield role and it suits him better. Today we saw, how he can create chances in small spaces and today it's more difficult to find such player, then an attacker - who is able to finish chances created by playmakers like Phil..
One day, I hope we will see Jack as LCM and Phil as RCM.. One day...