Why would compensation be the decisive factor for top talent in a highly compensated field? They have probably already made enough money that they don't have to work for living, and they are probably genuinely interested in their work because they made it to the top. Apple processors are already in the market, so the most interesting work is done, and it may be time to start looking for new challenges.
The article specifically lists culture and money as the reasons people are leaving. It also adds that there is a need for a challenge amongst a successful and accomplished group.
“ The bleeding hasn’t stopped in recent years as Apple’s work culture simply isn’t the best and other firms, namely the hyperscalers such as Google, Microsoft, Amazon, and Meta, are paying more than Apple was to poach talent.”
If you consider Maslow's hierarchy of needs, you have "esteem" at a high place. Money becomes a proxy for that.
Big management negotiate higher pay all the time not because there is a difference between earning 30 or 40 millions, but because they need to feel their own "value" go up.
This is discussed at length in "thinking fast and slow", iirc.
Spending goes up with compensation in general. Then it becomes the norm and you don't want to lose it. Sure you can retire but probably not at a level where you can fly first class everywhere, stay in five star hotels and stay on private islands.
That aside once people have kids the sky is the limit for giving them the "best life possible." Nanny, private tutors, private schools (and/or a house in Cupertino since it's Apple), college funds, house with good amenities nearby, etc. I probably missed some costs in there.
Private schools aren't the norm in the Bay Area, they just fund their local public schools more and then keep out anyone they don't like via NIMBYism.
They're more normal in SF because of the school lottery system which can assign you to a school whether or not you can actually get there on time every day.