Wouldn't be surprised if it had more to do with their expertise with carbon fibre than anything else. You're not going to find anyone with more expertise with that material than F1 teams.
Pagani have a separate company dedicated to carbon composite manufacturing and consulting - they came up with the "carbotanium" bonded carbon composites and titanium used in the Huayra:
Combine this with Tesla's acquisition of CF expertise, and I would wager that more CF is going to be used in electric vehicles in the near future, providing even greater range.
So long as money is no object, you're probably right.
Apple reportedly took great interest in BMWs carbon fibre mass production processes during the early stages of Project Titan, when Apple was rumoured to be courting BMW for a potential partnership.
Perhaps next year's iPhone. I've been thinking about how they can go to wireless charging without looking cheap. I think carbon fiber could be a decent replacement for the metal.
Maybe.
Note that these kinds of composites are exceedingly common these days.
Like "I can buy it online from amazon.com" common for some and "random online metals shop" for others.
Now certainly, not what Apple's gonna do, but more in the point of "there's a very very large set of companies with large amounts of expertise in this". I have pretty strong doubts you'd go to mclaren for it.
Apple's cases are nice, but "the best work in the world with [aluminum]" is a real stretch. They're not complicated or high precision, they're computer cases.
There are people making turbines with aluminum, and medical equipment, and machine parts that are accurate to an order of magnitude more than Apple's pretty phone case.
You can buy a lot of materials, but knowing how to manufacturer with them is a different skill. BMW has more experience with carbon in automobiles, but that's a whole other level of acquisition.
McLaren built an entire car out of carbon fiber. Good luck figuring that out from your Amazon purchases.
Material availability isn't really the issue, although supply is still very constrained due to the dominance of the aerospace industry.
The real issue is expertise. High performance composite manufacturing techniques are jealously-guarded trade secrets. The amount of information in the public domain is really very limited.
I suspect this has to do with their battery expertise as much as anything else. If Apple is looking to get into the Electric car game, the McLaren would be an especially good acquisition.
https://en.wikipedia.org/wiki/Carbotanium
https://en.wikipedia.org/wiki/Pagani_Huayra
Pagani make McLaren look mass market!