Claudius We aren't unlocking defences by upgrading Kolasinac and Martinez with Tomiyasu and Raya.
Martinelli, as much as I love him, isn't a top end technical player. Nor is Havertz. Jesus - great dribbling, good touch, great fight - not elite. Rice, not elite. Odegaard, Saka - proper top end stuff - but we don't have enough players supporting them on their level. Partey and Jorginho, both great technically but with massive drawbacks in other aspects of their game - largely fitness for different reasons and unreliable as a result. It makes it too easy to crowd us out of games.
So yeah, we've got a great, and enviable, level of technical skill in the back line but Gabriel and Saliba aren't picking apart deep defences. It's great against 80% of the league and is a huge foundation in getting us to this point, but to make the difference at the top end we're going to have to add a bit more guile and craft to that, and almost as importantly, have conviction in that ability.