Wireless isn't going to completely replace the wired connection on mobile devices for a VERY long time. As for digital audio, USB-C will be the standard in just a few more years, only a complete Apple fanatic could think otherwise (and I'm saying that as an engineer that worked at Apple for many years and who also owned the very first models of the Mac, iPod, iPhone, iPad, and Apple TV).
I'm very aware of where the industry has been and I think I have a good idea of where the future lies (and it isn't with the Lightning port). The Lighting port was a good idea when it was first introduced, but that time is now gone given USB-C.
I guess I should add that I'm not predicting that Apple will actually route analog audio over the Lightning port, I'm just saying that they could and that it might happen.
I think the most likely outcome is that Apple will just remove the 3.5mm headphone port and offer only digital audio out, but that's going to make a good number of customers (or former customers) pretty upset (IMO).
Even if USB-C does become the digital audio standard in just a few more years, it's still not going to replace the 3.5mm connector on everything else. So people are still going to need adapters, which means it doesn't matter whether it's USB-C or Lightning, for many, many more years.
Your claim to being an Engineer who worked at Apple is somewhat dubious, which is somewhat confused by your insistence of an analogue output adapter from Lightning, especially when you say that the absence of one will drive customers away. But in the same post you talk about an all digital USB-C port being the "standard" mobile audio output very soon. So which is it? Customers will leave Apple to keep their 3.5mm Jack, or to embrace USB-C and go all digital because everyone is going to eventually remove the 3.5mm Jack. I can't figure out exactly what your issue is here -- you want Apple to offer analogue audio that requires an adapter, but want them to switch to USB-C and then it's OK if they don't offer analogue audio?
Add to that, as an Apple engineer you seemed to have a fundemental misunderstanding about how the 30-pin to Lightning adapter works and why it's important to your point that Apple chose not to provide analogue audio over Lightning.
Yes, the other Macs will get USB-C but NOT Lightning (you can be absolutely sure of that).
Because you're a former Apple engineer who owns one of everything Apple has made?
Sorry, you're entitled to your opinion, but that's all it is unless you want to post your linked-in details to confirm your engineering pedigree and insider knowledge.
What I'm sure is there's no way Apple will remove the headphone jack and force customers to use their new Lightning headphones with an adapter on their new MacBooks. Plus there are a number of compelling reasons to add a Lightning port to the MacBook, in line with what they've already been doing with Lightning.
I'm more sure this might happen than you are of analogue over Lightning.