Ask HN: How do high “value” targets protect themselves against exploits?

So I just read about the NSO 0 click exploit posted on HN.

I was wondering how politicians, well known business people, think senators, fortune 500 CEOs etc, protect themselves against these kinds of exploits or even less sophisticated ones?

Does Apple sell custom solutions for such users? Do they run 3rd party software that locks down their phones? Do they physically modify their phone's hardware in some way?