So I just wasted 6 hours trying to get macOS in KVM to run on an iGPU. I am writing this here to remind myself that it doesn't work because q35 machine type is required for macOS with passthrough, however iGPU passthrough requires i440fx machine type. This is for legacy passthrough where macOS would be on the laptop's screen itself. And new iGPUs don't support this afaik. Oh what could have been...