My guess is that this was planned in an era (sadly now) where open space is portrayed as the "cool" way to work.
Pretty much, the open space hype seems to have peaked in like 2010-2012, now we live in an enlightened time where even corporate leaders (gasp) are willing to admit different things work for different people.
I'm sure Jony Ive has an office.
Yes. Once I see all the big shots sitting elbow by elbow at a long table the whole day I will revise my opinion about open offices.
Musk and Zuckerberg "sit" among the peasants. It makes for a good photo op but in reality they have to spend very little time at their desk. At that level, they probably spend most of their time in meetings, and even when not, it's not like anyone would chastise them for behaving inconsiderately to other people in the office, or taking over a conference room as their impromptu office.
Same with Jack from Twitter. At that point it's just an empty gesture.