Technology

Except the boot process on a non apple PC is open software.

For the most part, it isn't. The typical laptop you buy from the major manufacturers (Lenovo, HP, Dell) have closed-source firmware. They all end up supporting the open UEFI standard, but the implementation is usually closed source. Having the ability to flash new firmware that is mostly open source but with closed source binary blobs (like coreboot) or fully open source (like libreboot) gets closer to the hardware at startup, but still sits on proprietary implementations.

There's some movement to open source more and more of this process, but it's not quite there yet. AMD has the OpenSIL project and has publicly committed to open sourcing a functional firmware for those chips by 2026.

Asahi uses the open source m1n1 bootloader to load a U-boot to load desktop Linux bootloaders like GRUB (which generally expect UEFI compatibility), as described here:

• The SecureROM inside the M1 SoC starts up on cold boot, and loads iBoot1 from NOR flash
• iBoot1 reads the boot configuration in the internal SSD, validates the system boot policy, and chooses an “OS” to boot – for us, Asahi Linux / m1n1 will look like an OS partition to iBoot1.
• iBoot2, which is the “OS loader” and needs to reside in the OS partition being booted to, loads firmware for internal devices, sets up the Apple Device Tree, and boots a Mach-O kernel (or in our case, m1n1).
• m1n1 parses the ADT, sets up more devices and makes things Linux-like, sets up an FDT (Flattened Device Tree, the binary devicetree format), then boots U-Boot.
• U-Boot, which will have drivers for the internal SSD, reads its configuration and the next stage, and provides UEFI services – including forwarding the devicetree from m1n1.
• GRUB, booting as a standard UEFI application from a disk partition, works like GRUB on any PC. This is what allows distributions to manage kernels the way we are used to, with grub-mkconfig and /etc/default/grub and friends.
• Finally, the Linux kernel is booted, with the devicetree that was passed all the way from m1n1 providing it with the information it needs to work.

If you compare the role of iBoot (proprietary Apple code) to the closed source firmware in the typical Dell/HP/Acer/Asus/Lenovo booting Linux, you'll see that it's basically just line drawing at a slightly later stage, where closed-source code hands off to open-source code. No matter how you slice it, it's not virtualization, unless you want to take the position that most laptops can only run virtualized OSes.

I think you mean that Apple uses its own memory more effectively then a windows PC does.

No, I mean that when you spec out a base model Macbook Air at $1,199 and compare to similarly specced Windows laptops, whose CPUs/GPUs can deliver comparable performance on benchmarks, and a similar quality display built into the laptop, the Macbook Air is usually cheaper. The Windows laptops tend to become cheaper when you're comparing Apple to non-Apple at higher memory and storage (roughly 16GB/1TB), but the base model Macbooks do compare favorably on price.