Ok lets get serious now: the only adequate reason for keeping an injury-prone high earner would be if he was absolutely unplayable when fit (i.e. Robben). Does Dybala even come close to this criteria? Nope.
Just because he's OUR most technical player doesn't mean he is good in European standards, it just means we are very shit technique-wise as a team overall. This is a player whose prime form is 'good player' level at best.