For all the people talking about 5 hour PR review delays... This reminds me of some teams that rotate the "fire extinguisher/emergency bug fixer" duty every day/week/sprint to a different developer. One could rotate a dedicated "first review duty" person. That developer would be in charge of focusing on rapidly starting PR reviews as their priority, with option to request other reviewers if necessary. Spreading the duty around would make people be respectful of the reviewer because if they send unreviewed slop to the reviewers, it's likely that people will send them slop too.
It's not impossible that the Pentagon could have thought "alright, we want these readings. is there a civilian use for this kind of data and decided to see if a civilian project could be sprung up... Though that's more of a Cold War conceit. These days they would just do it themselves, it's probably an easy and cheap project.
Okay but the solution here is to identify and parcel your cases into discrete entities. The article doesn't say "don't accept anything odd", it says "clearly identify what you accept". If you have to accept odd cases, identify them so it's clear what's happening.
So this isn't about purity, it's about being declarative. i.e. make your code say what it accepts, instead of writing board/implicit acceptable inputs that inevitably forget cases and crashes.
If you limit what you accept as inputs then you can stop worrying about downstream error handling and debugging.
Half of developers in North America, and especially those at top tier companies, use Macs. You can't buy that kind of top tech mindshare with marketing. Also now with the M-series CPUs, Macbooks aren't PC Clones anymore, they're back in the game of being an exclusive platform, which will get even more exclusive as they add other specialized chips. Their sales share of the market and as you mention, their profit share of the market keeps increasing, so even on that alone, why would a bean counter decide to drop them?
Don't forget Apple's size... the AirPod business, stood alone, would be a Fortune 500 company. Even if an Apple business is a bit small compared to the iPhone, it's still a humongous business by any other comparator.
I'm not an Apple fanboy (e.g. I use an old Chinese Android phone) but I'm still awed by their business.