The actual truth is... this ain't never gonna happen. Never.
…and not for any technical reason: Microsoft makes money by licensing software and services for the huge range of third-party Windows PCs on the market. Their own Surface line is way down the market share list below HP, Dell, Lennovo, Acer, Asus, et. al. buried somewhere in “Other” on most lists. I can’t see any good reason for them to allow, let alone invest the non-trivial effort of making an Apple Silicon version of Windows-on-ARM, unless Apple are going to start selling SoCs to HPDelnovo (cue flying pigs, hell freezing over and other portents) so they can start churning out M-series PC laptops en masse.
The current state of the art is that a native Apple Silicon Windows on a M4 would likely blow other Windows-on-ARM platforms like Snapdragon out of the water - and there’s no real competitor to the M4 Pro and Max (it gets more interesting once you get to server-grade ARM CPUs). That would tick off the rest of the PC industry somewhat, and MS can’t afford that).
All the other technical problems could be solved, given that MS would need to make a modified kernel anyhow - we aren’t likely to see a hacker-led solution like the one that prompted Apple to release Bootcamp.
Meanwhile, MS will struggle to shift Windows users from x86 to ARM because, again, they have to take the entire PC industry with them, and the industry has to persuade users to put up with the inconvenience of the transition, whereas Apple simply declared “We’re not making x86 Macs any more - deal with it!”