Yep, I don’t trust this very much. Two of the same iPhones that are fully updated and in the same region should be essentially indistinguishable by the things they mentioned.
They promised that the tech would always give a stable and unique id from the browser. And it worked too, but it wasn't public and not for ad tech purposes.
I have a POWER9 desktop, and a fair share of other users do so for privacy/security concerns, pretty hardcore Tor browser guys and the like. I've mentioned before that fingerprinting firefox on ppc64le would be very easy because of timing the non-JIT'd JS engine. I guess there's potential for much more specific fingerprinting.
How would you defend against that profiling tech?