Even a raspberryPi will boot and run windows for arm without virtualisation. You can be sure MS haven’t made a custom version just for them.
Actually, MS did officially release the "Windows 10 IoT Core" for Raspberry Pi - as the name suggests it's not the full Windows desktop OS but it could explain why the Windows kernel can be persuaded to run on the Pi. Also, the Pi uses a Broadcom system-on-a-chip which
wasn't made exclusively for the Pi, so it's possible that Broadcom or MS have written Windows drivers for the GPU etc.
However, the real point is that even though - even after a lot of hacking from the
large Pi community - WoA will boot and run on the Pi, it's pretty unusable, and lacks a lot of essential drivers. There's a lot more to producing a stable Apple Silicon version of Windows than just producing a bootloader.
Apple hasn't put any effort into it (e.g., an ARM version of bootcamp) because there's no legal way to run it on their hardware as yet.
There's apparently been a legal (if unsupported) way since about last October when it became possible to install & license a "production" version of W11 on Parallels without going through the insider program. I say "apparently legal" since it doesn't involve signing up to an evaluation program Parallels have been openly advocating it for the best part of a year and haven't been sued into a smoking hole in the ground.
Bootcamp for Intel Macs probably only happened because it was "low-hanging fruit" and Intel Macs were very, very close to being regular PC clones - all that was needed was to add a BIOS compatibility module for EFI and you could pretty much just install and run a a regular Windows installer DVD & then hunt down bog standard drivers from Intel, AMD, NVIDIA et. al. Apart from that, Bootcamp was really just a point-and-click tool to help regular users partition disks, tweak the Windows installer and set up a dual-boot system.
Making Windows-on-ARM run natively on Apple Silicon isn't
impossible but it's a lot more complex than Bootcamp ever was and would probably need
both Microsoft and Apple to collaborate on that... and why would they?
Apple Silicon is, for the moment, way ahead of anything Microsoft/Qualcomm produce - with properly optimised drivers, WoA on M1 would thrash any other WoA machine currently on the market (the reports from people running WoA on Parallels are enough to predict that). That sounds cool - it could even be the thing that makes the industry take WoA seriously - but at the expense of MS handing Apple a near-exclusive on ARM PCs.
Microsoft may make a small, strategic range of "Surface" PCs but their real business model is software and services - the backbone of the PC industry is Dell, HP, Lenovo et. al. and an army of smaller PC makers who will be seriously ticked off if they can't compete (and Apple ain't gonna be selling Apple Silicon to Dell anytime soon). What MS will want to see is a future Apple Silicon-killer from Qualcomm or suchlike that other PC makers can use. Endorsing Apple Silicon now would set an awfully high bar, and encourage direct comparisons between Apple and PC hardware, without OS differences getting in the way (currently, many Windows customers won't care if the M1 is better if it doesn't run their software).
Apple's main interest is providing a hardware platform for MacOS and
their software and services - and a big part of the switch to Apple Silicon was to allow them to tightly link their OS and hardware. They've got a big head-start in terms of performance vs. power consumption at the moment, which is great for laptops, but at the higher end they're already very dependent on software being optimised to take full advantage of Apple Silicon. As other chip makers play catch-up on raw power, the tight integration between MacOS and AS is going to become their main selling point. Committing to supporting any 3rd-party OS (especially Windows, who's users tend to be obsessed with backwards compatibility) - would put constraints on how radically they could change future hardware, whereas now they only have to worry about MacOS.
...plus, of course, for the many people who just need Windows for a few apps not available for MacOS or testing, virtualisation is the better solution anyway - c.f. having to inflexibly partition your SSD, reboot every time you want to switch OS, and getting Windows to read/write APFS and/or MacOS to write to NTFS etc.
