I'm starting to strongly dislike that article, because I've seen it posted multiple times as proof of Macs going ARM and it's a crummy article. There are two problems with it:
1) Quoting another website that is talking about private conversations with people who work at Intel. Intel hasn't heard anything from Apple and as far as we know these officials don't have any data to go off of, they're just speculating like you and I. Yet the article headline talking about "Intel expects..." makes it sound a lot more official than that, doesn't it?
2) Marzipan is being quoted as some proof that Macs will go ARM, which doesn't really make sense. We're already seeing the early fruits of Marzipan in the form of Catalyst. Yet what is Catalyst enabling? iOS apps to be ported to x86 Macs... not the other way around. What it's really doing is allowing iOS developers - who I'd guess outnumber Mac developers - easier access to the Mac, which should theoretically also increase the number of programs available on the Mac, which could in turn revitalize the Mac ecosystem. It doesn't mean that Macs aren't going ARM, but it's definitely not proof that Macs would need to go ARM, given that Catalyst is already happening with x86.
Apple will need to tread incredibly carefully if they want to switch away from x86. Aside from bringing development in-house, it's not entirely clear what benefits they would gain from ARM, either. Their MacBooks are already class-leading for battery life and size, and performance is surprisingly good - I used one as my main computer for a year, even running Capture One Pro and Final Cut Pro on it. Desktops would probably have zero benefit, and all at the risk of alienating other developers and mainstream software that many Mac users currently rely on. And while I can't speak for everyone, much as I enjoy my iPhone and iPad, my computer is still my #1 device. If I'm no longer on a Mac, the strength of having multiple Apple devices that speak to each other greatly diminishes. Microsoft's Surface is a compelling iPad replacement, particularly if my main computer becomes a Windows computer, and while there's no longer a Windows phone, Android is... well, I'd probably stick with the iPhone
But the point is, Apple would need to make a very compelling case for the architecture switch, one that would give enough benefit to their consumers that the negatives would be outweighed. I don't have any special behind-the-scenes information to back up my opinion, but based on keeping up with technology news, I just don't see the benefit nor the appeal beyond making things easier for Apple's management. That's a poor proposition.