Thats impressive speed for an install that not just copies pre-installed system, but also includes Hardware detection and selective driver installation phase.
AFAIU the part that's doing it here is also the Linux part of the installer, so Linux either way. But I feel Windows was always slow with getting new devices ready at least until Windows 7, 8.1 felt much better, no idea how current 10/11 fares.
That's not their point? Linux has all the drivers lying around on disk and on every boot just does hw detection and loads the appropriate ones. It takes a few seconds. You can take a Linux install from a modern AMD system, stuff it into a 10 year old Intel system and it will boot up instantly. No driver install no "getting your devices ready" screen that shows up for a minute or two.
This has nothing to do with being open source or being customizable. It's simply pointing out how fast hw detection is not only possible but the norm on other systems.
PCI wasn't a given. Plug and play wasn't a given. You couldn't even reliably enumerate all hardware on a system.
Hardware detection back then involved a lot of poking at random IO ports and seeing what happens, using heuristics to select an appropriate driver. This is as dodgy as it sounds and would crash or hang your system if you weren't lucky.
One thing that helps this is that most of that really buggy hardware has fallen into the wastebin of history and everything attached to a "modern" W98 machine should be plug and play compatible. PCI solved most of these issues. ISA cards gave Windows 98 and especially 95 a bad rap. Well, that and early USB controllers and devices. There was a whole lot of brand new driver code being tested in production back then.
Thats impressive speed for an install that not just copies pre-installed system, but also includes Hardware detection and selective driver installation phase.