The change introduced in commite5b072eca1breaks backwards compatibility for some users, seee5b072eca1 (commitcomment-113775008)https://github.com/NixOS/nixpkgs/pull/219351#discussion_r1139773448 This change updates the implementation to enable BIOS boot if possible for the build and host platforms, and also assert that BIOS boot is not enabled for non-x86 host platforms.