Building these binaries and their dependencies with both architectures will allow the binaries to run natively on either x64 or arm64 developer Macs.

./autogen.sh in the ios_usb_dependencies recipe is called here:
https://flutter.googlesource.com/recipes/+/refs/heads/main/recipes/ios_usb_dependencies/ios-usb-dependencies.py#276
via the resources sh scripts, like:
https://flutter.googlesource.com/recipes/+/refs/heads/main/recipes/ios_usb_dependencies/ios-usb-dependencies.resources/libimobiledevice.sh#24

I believe exporting CFLAGS="-arch arm64 -arch x86_64" env variables will configure and later build/make with both binaries.

See how the libimobiledevice GitHub action does this:
https://github.com/libimobiledevice/libimobiledevice/blob/149f7623c672c1fa73122c7119a12bfc0012f2ac/.github/workflows/build.yml#L141-L164
https://github.com/libimobiledevice/libimobiledevice/actions/runs/16663185556/job/47164554420#step:10:23

Part of #69157