I also don't have a horse in this race (used the latest & greatest from both Apple and Microsoft/Intel/Nvidia), but I don't think you're seeing the entire picture either.
First off, Apple hasn't won. There are still markets they don't cater to (budget computing, HPC, gaming, machine learning research, CUDA programming, 3D design/rendering, native Docker development, the list goes on), and they show no interest in poaching those users. Second off, you're overestimating the impact of Apple's advances here. Performance-per-watt is a nice advantage, but it came at the cost of abandoning x86 and paying insane up-front costs for next-generation silicon that led to a disappointing M2 cycle. One thing is certain, though - Apple's performance entirely relies on their ability to out-bid competitors for competitive components, which gives them a default monopoly (as the richest company in the world).
> What do you think Apple will do to Microsoft, once Microsoft products are primarily accessed over Apple devices?
Apple will do the same thing they've always done, beg third-parties to stay on their platform with under-the-table deals that bolster support for the App Store. Microsoft makes Apple money, to remove Office365 support would be paramount to telling your business customers to pound sand. All of this is ignoring the antitrust regulation mounting against Apple for their completely unfair abuse of the App Store and software distribution. Even still, they will never have the leverage to kick Microsoft where it hurts because they'll never have competitive market share. Like I said in my previous comment, assuming the most absurd conditions (like Mac sales growing 30% YoY), it would be decades before Apple had enough control to pull that off.
I hope you're right, and Apple tries to act cute while the trade commissions are watching. We're long overdue for another nuclear platform abuses lawsuit like the one we stuck Microsoft with in the mid-2000s, all it would take is one silly move to push us there.