I've not read through this thread, but here is my opinion.
Brooklyn has had a front row seat to his parents' marriage, which is highly rumoured to be dysfunctional, but one which neither will leave outside of a coffin.
Ms Peltz's parents' marriage is not a concern of decades long rumours of infidelity, outside children, sidepiece NDAs, having to smile at functions where one's husband has more than one ex sidepiece in attendance and him having a best friend (not Mr Neville) who is an enthusiastic wingman who shares the same "community dick" activities.
Brooklyn has escaped them and their pr and their need to be seen as a close knit family .
As indolent as she appears, it could only be a straight shooting American who would show Mr and Mrs Beckham that they.are not the boss of their son.
Worse, she comes from wealth which makes them look like Hurry Come Ups.
And I bet that Brooklyn has found a real confidante in Nicola.
All of the Beckham boys seem listless with Harper being the Golden Child.