Kim is 25 and Timber is only 21, so Timber still has time to learn. Timber himself felt he wasn't ready for United and that is why he stayed at Ajax and we signed Martinez (24) instead. Those three and Ndicka (23) puts us in very good shape for the next 5+ years as Varane's (29) career winds down.
I agree with letting go of Maguire, Lindelof, Tuanzebe, Jones and Bailly, and three replacements doesn't sound excessive, especially when Timber can cover Dalot and Frimpong (?) at right back as well. Hopefully we can get enough funds from the leavers, and AWB, to cover most of the purchase price.
I was someone who really wanted Timber in the summer but in the lovely world of hindsight I think we've made a much better decision signing Martinez.
We needed someone to come in and really nail down the spot (largely to kick Maguire out of the side for good) and although I think Timber has amazing potential, I doubt he would have been able to take to the league so quickly and perform to the level Martinez has.
When you think about it as well, how many successful top sides have a 21 year old in the CB pairing?
Between 23 and 25 years old seems like an ideal time to make first team signings at CB, where the player has the right balance of experience and potential. Martinez fits that bill, as would both Ndicka and Kim...
Perhaps more realistically we sign Ndicka this summer and plan for Kim in 2024 after another year in Naples, then who knows, maybe we pick Timber up when he's 24/25 after a middle move elsewhere for him to gain enough experience.