I wonder the same thing for my regular OS too. Sure the first time it boots on this hardware, it needs to see what's what. But the subsequent hundred/thousand boots, at least for my usage, will be identical.
Before you can reload some previous known state, you need to initialize the hardware, load the firmwares and probe the devices (USB, SATA, PCI), discover the storage volumes and the partition tables. All these steps take time.
That's kind of the point of Windows' Fast Boot option. The base OS pretty much just hibernates at a normal shutdown. No point in re-initializing and restarting all the base services.
There is also often a UEFI option for a "fast boot" as well, where it skips some steps in its initialization, doesn't wait for any user input or logging to the local console if its coming back from a successful boot/power off cycle. But that's separate from the Windows feature which is related to hibernation. You could have Windows Fast Boot enabled while having your UEFI set to a full boot cycle or vice versa.
The UEFI option should work fine with pretty much any OS the hardware should be able to boot.