Though it doesn't invalidate the gist of your saying, malloc is a user-space function not a syscall. (Its implementation will occasionally do a syscall, such as to sbrk or vmmap.)
Lockdown Mode was added in iOS 16. The article only mentions iOS 15.7, saying there is no information whether iOS 16 is vulnerable (with or without Lockdown Mode), unfortunately.
It's curious they say iOS 16 was released "last month" when it was released last year.
But it's not that simple. Startups are always measured against their competitors. So even if the 1/(1-n) shows that it is a net gain for me, it may be an overall loss if my competitors make deals that are worth significantly more for them.