Not sure it's been said here but the current trend seems to be play more CB's(invert to 3 in attack).
City and Arsenal both did it last season and in the community shield Arsenal played with Saliba, Timber, White, Gabriel(4).City had Akanji, Stones, Dias(3).
I think what we've seen in preseason is Unai position us to also play like this. I feel its good news to be ahead of the curve on this to be one step ahead of other top 5 pretenders (Newcastle, Spurs, Liverpool, Chelsea).
To sum it up I'm just happy to be on the cusp of a possible football evolution instead of just watching it all unfold.