With Saibari, you have a player who can back up Kane, so you no longer need an extra striker like Jackson.
Playing Saibari at 10 makes Musiala available for other positions, e.g. left wing or even 8.
Simply put, you have upgraded Jackson and Guerreiro with one top player.
I’m wondering what exactly the plan is, because Musiala, Saibari, and Gnabry simply feel like too much for one position, not only in terms of the minutes that need to be distributed, but also when it comes to the wage bill tied to a single role.
I would consider it a suboptimal solution, but it seems quite likely that no additional left winger will be signed and that Díaz’s backup will come from the pool of those three players.