It's not about 8 fullbacks and central defenders, it's about Pep, who 2-3 months ago said, that he would love to work with the smaller squad, like 16-17 players and 5-6 academy players who are playing at a top level and can be used throughout the season..
According to Pep, this kind of squad is easier to motivate, manage and also - you build nice cycle from academy to the first-team, where every department is involved and has idea, about the future.. And TBF I like this as well..
Why you should sign some shitty CB as a fourth choice to play 10 fucking games at max a season, when you can give those minutes to Mbete and therefore contribute to the development of academy product.
Same applies to attackers and midfielders.. Those 10 games can be played by Palmer and Macatee and I also thought that young fullback If I am correct -> Egan Riley - was ready to step up and play this year, but he went to Burnley instead.. (But that's OK, Vinny will make him even stronger..). Same applies to Bazunu..
But Palmer-Macatee-Mbete-Kayky I think are the top talents and need time.. If Riley and Bazunu had stayed, this would make 6, like Pep predicted..
Ederson Ortega - (Bazunu)
Walker Cancelo Cucurella - (Riley)
Stones Laporte Ruben Ake + (Mbete)
Rodri Phillips - (Lavia)
KDB Bernardo Gundogan + (Macatee)
Foden Grealish Mahrez + (Palmer / Kayky)
Haaland Alvarez - (Delap)
19 players, if we had sold Ake and Bazunu stayed as N2 - it would make 17 + 6
So, no need of this 4-th shitty / average players, when you can help academy talent and grow players like Foden & Palmer..
Hopefully, year-by-year - we will come closer to Pep's formula..