I'm actually quite impressed. 1) He stood up for his wife. How many men just shrug and let their wife deal with the shit? 2) He potentially threw away £100m+ in inheritance to do so! I wonder if the Beckhams just assumed he would never dare do something this because they themselves are so enamored with £££. So they thought they could pretty much do what they liked and he would have no choice but to toe the line. Well, they just got burned.
I actually assume that he tried to resolve the situation in private for a long time. This is the first time he has spoken out in public and it comes after a prolonged smear campaign against him and his wife in the media. If his parents had respected his wife and his wishes for distance / peace it might not have come to this.
People going on about how he wouldn't have done it if his wife wasn't rich: 1) His wife is not that much richer than him at this moment in time. Her father is, but old Peltz won't hand his money to Brooklyn, that's for sure, and Brooklyn certainly knows that, too. He also 100% signed a prenup, so he won't see a penny of her inheritance. 2) I think that being finally happy and secure (yes, including financially secure, even if not on the scale of his parents or in-laws) just accelerated the process. Of course Brooklyn waited until he was financially independent. The mind boggles that anyone would expect otherwise. It is very hard to escape financial control unless you have some money of your own!
I think financial control is also the reason his siblings haven't broken away yet. Although I have some hopes for Cruz. When he explained his (awful) song lyrics he too tried to make the point about image mattering more to some people than others. Though if Cruz steps away in a few years, I expect he will do it in a more low-key way. The oldest sibling is often the one who has to make the biggest effort to break free. The parents will be more cautious with the younger siblings.
Finally, in my opinion, none of what his parents have given him (including his wife, as people like to point out for some reason) justifies his dysfunctional upbringing and the frankly really weird media campaign against him and his wife. I used to think that the Beckhams are basically good parents and their very obvious bad decisions (parading and occasionally humiliating their children in the media for clicks) was just because they genuinely didn't know better. Now I think maybe they are full-blown narcissists after all.