It's not all Pickford's fault, but there is a significant amount of data that suggests he is not very good at saving shots, which remains the core role of a Keeper, despite the increased need to a quarterback / distributor of the ball.
Pickford has an average save % of .632 this season, the 15th worst (of 19 who have 1000 mins or more) in PL, that is based on 87 shots on target conceded this season. Should we have a keeper delivering an "Average" save % of 0.701, based on the 19 keepers, you are talking about 6 goals less conceded; which weighted over the entire season would be 10.36 goals.
That is a massive shift in your defense.
If he wasn't English and somewhat immune to national criticism as a result, he would be a championship keeper know for pulling off the odd worldy