The same can be said for aluminum, but still Apple is known for doing some of the best work in the world with the material.

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.

https://www.wired.com/2016/06/mclarens-675lt-supercar-someho...

BMW, McLaren and friends probably simply buy all the carbon fiber they use from Toray. Just like Boeing do.

If McLaren has some production, it's probably not more than a pilot plant.

It's not actually producing carbon fiber that is the secret sauce.

BMW co-owns a company called SGL Automotive Carbon Fibers.

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.