He should have been getting it here. Cancelo has been dreadful for a long time and yet Zinchenko was still only getting in the team from January onwards every year (and we always improved after he got back in).
The reason Jesus, Sterling and Zinchenko all felt the need to leave was that one of the crucial parts of Pep's philosophy - that he'll pick the XI that deserve to start, not the biggest names - was completely obliterated last season. If I was watching Cancelo dropping clangers from the bench, or Grealish picked over me despite being well below his best, I'd want to leave too.