Who mentioned najd?
Ones from najd became custodians.
So?
They are arabs are they not?
How are Hashemites - who currently are in Jordan - come from the Quraysh - ok to rule this area of Levant then?
They actually ruled Hijaz through the British and are actually from Makkah... was that also objectionable to you?
Hijaz was ruled by people with origins in Syria, Iraq, Egypt - far away - did you cry a river for them?
I get the single Hadiath on Najd in Bukhari - while Muwatta which is the older text only says east - which drives the core of the modern attack against the house of Saud.
That was first used(in its uncollected referenced format prior to it even being compiled as a Hadith) "weaponized" back against the Khwarij of Iraq because they were from the east and practiced Takfir - and then later by Ottoman and Hijazi ulema against Abdul Wahab because he practiced Takfir.
Back then it was just the east - in this context it became the area of Najd.
That does not absolve that the Saudis have not collaborated with the west or otherwise - nor does take away that your argument that someone from Najd cannot be custodian of the mosques is completely invalid.
Unfortunately, your bias is now extremely visible for reasons I don't want to speculate on - and that is also proving your logic and even a moral or ethical stance on the situation a house of cards.