> Ironically, Windows 10 and 11 easily have the smoothest install of any version of Windows ever.
Since introduction of WIM it's the same for all versions. WIM was introduced with Vista.
> It's still a mystery to me why every other version of Windows is terrible.
Because you conditioned yourself on the meme-train. There is no 'bad' Windows, there are just new versions which were needed to pave their way for the new tech.
Chicago really pushed the availability of the computer for Average Joe.
Millenium was a swan song for 9x line and included a bunch of tech from the business line to improve the reliability of the OS, including Automatic Updates, which were promptly disabled by k3w1 h4x0rs to 'save resources' and to 'fuck with Bill'.
Vista had a ton of internal changes like integrity levels, new WDM and WDDM (finally the graphic drivers crash didn't mean 100% reboot of the system), totally revamped WinSxS (I think you forgot what DLL Hell was - Vista is the OS what hit the nail in the coffin) and a ton and ton of things what you probably think came in Win7. It didn't help what MS didn't manage to tell the OEMs to fuck off with their shitstock and hence - 'Vista Ready', using 4200RPM drives with 512Mb of RAM. In 2007.
Win8 was a difficult beast, which should had transform the human-computer interaction but again manufacturers told MS to fuck off and that's why there is still only 10% of notebooks with a touchscreen on the market. Everyone shat on Windows Store while simultaneously happily blowing the walled garden of iOS (and Play Market and Steam were a thing too, for years at that moment).
Win11... yeah, this is shit. The development was taken over by pumpkin latte guys with McAirs who for sure doesn't eat their own dogfood.
Also people forget (or don't even know) on what awful hardware Windows runs sometimes yet it's always Gates himself who is at fault what a cheapass Shitsco 9999 with a bubblegum instead of a thermal paste BSODed again. Hey, man, if you got IRQL_NOT_LESS_OR_EQUAL that it's 90% hardware, 10% drivers of the said hardware. Mac fanboys really love to boast about stability of their shiny overpriced shit, without even thinking about how many variations of HW (even without HW revisions) there are for Apple computers and for Windows computers.