[em3rgent0rdr]

Well it is a separate package because it is fundamentally independent of the kernel. For example, your Debian system might want to use a different kernel like GNU's Hurd, kFreeBSD, or NetBSD, so by keeping those packages separate, they can easily be used interchangeably. Also if you are on an AMD system, you wouldn't want Intel microcode, but you might still want the same Linux kernel.

Also another big issue issue is the Intel microcode is proprietary, so separating it from the kernel means that user could selectively pick and choose if wants to have a totally free system, which would mean not loading microcode updates with a libre kernel. This is done for instance with Parabola and Trisquel distros, which is needed to obtain FSF's totally free certification.

[orblivion]

Does this mean that my Ubuntu installation runs stock Intel microcode? It means I actually have to know about this, and then go out of my way and know how to install it? Or should it be installed by default on Ubuntu? Because the package called `intel-microcode` isn't installed for me now.

[SmellyGeekBoy]

This is an excellent explanation. Thank you.