People keep bringing up the very tired “Linux on the desktop” meme to dismiss the Fediverse.
But a meme is just a meme.
In the real world, Linux dominates.
Your phone? Probably Linux. Your car’s infotainment system? Linux. Your router? Linux.
Chromebook? Linux.
Windows has a Linux Subsystem too.
Linux has won.
The “Linux on the desktop” naysayers don’t even realize it.
The Fediverse should be so lucky.
I am not too sure either, but the Linux kernel is scalable so it can run on anything from embedded devices right up to supercomputers.
As a result you take the kernel and customise it so it just has the components needed, so a tablet has say solid state storage, so would be optimised for that you don't need the SATA support for example.
So the Kernel just then acts as a layer between the hardware and the android user interface.
I am probably wrong somewhere, but that is how I understand things. I would guess the Linux kernel for the Raspberry may not have SATA support built in, as there is no SATA hardware, but other single board computers may have that.