It still doesn't make sense for MS to push ARM that way - Apple isn't offering its ARM processors to 3rd parties. The best non-Apple processors are obviously x86 right now.
I'm deeply fascinated by these questions. I'd love it if someone in the chip design industry who is knowledgeable about the situation would comment.
Intel has been in trouble for some time due to its own failure to downscale, a failure which has little to do with x86. They'd be losing to someone else if Apple/AMD hadn't been there.
Intel still has some time to recover: it has plenty of money, and Apple/AMD are unable right now to take full advantage of their position. Apple/AMD rely on a supplier (TSMC) which does not have the capacity the supply all or even most of the processor demand, so Intel gets quite a bit of marketshare almost by default.
Imagine 3 years from now there are a bunch of Chromebooks selling at Chromebook prices, but offering intel performance. That would start to hurt Microsoft.
Chromebooks are only relevant in US school system.
Very few people are willing to pay the same price as a regular laptop for what seems just a big browser OS.
There are a good amount of chipsets that are now on 5nm processing. But only Apple made a full desktop OS to go with it.