Thank Koeman for his 70+ games in his first professional season. I'm pretty sure it fucked up his muscles in one way or the other.
He played the equivilant of around 40 full games for Barca that season in terms on minutes and club can balance that off v training etc. There had been a 3 month break from football that year before season started also.
The issues for Pedri came when he had the stop/start summer for Euros then Olympics then back to Barca quickly after few weeks off.
Then both Koeman and Xavi rushed him back once injuries started.
Folk are focusing too much on the number of games he played that previous season.. he coped fine physically with that and had played a lot of minutes season before.
The clear change was how the summer and into next season was handled then coaches handling injuries when started.