I imagine it would be a big lift. Asahi linux is managing through reverse engineering the hardware support, without any official documentation. Even with official documentation it would be a significant change from other aarch64 hardware.
I'm curious why I would want to dual boot Windows when there's a perfectly good hypervisor and paravirtualization built into macOS?
Arm-based windows support via Parallels does work, but AFAICT there's no official way to buy a Windows license due to a Microsoft/Qualcomm partnership.
Technically speaking, Bootcamp is an iBoot problem. Apple stopped shipping Macs with firmware UEFI which breaks 99% of generic OS installers out of the box.
Microsoft is pretty justified not wanting to support that, versus UEFI on OG Bootcamp. The majority of Linux distros don't ship image support for iBoot either.