The canonical firmware is the BIOS, I was pleasantly surprised when Fedora updated the BIOS on my Dell XPS device by itself recently... historically that has been somewhere between a nuisance (Reboot and then UEFI network update), a struggle (dig out the image from an EXE on a flash drive), or impossible (some windows-only app that doesn't work via a VM). And whatever the annoyance level, when done manually it was usually done months or years after the BIOS release.

Other firmware the cpu microcode is handled via packaging.

There has been a lot of work packaging peripheral firmware for things like mice... it's not like it is going to go away. This is also distributed in packaging in Fedora now.

It's not ideal that these are proprietary blobs but some accommodation is needed I think.