The difference is, that you could just continue using XP until Win7 was released or continue using Win7 until Win10 was released. Win10 will reach end of life next year and then the only supported Windows will be Windows 11. Vista or Win8 were never as forced as Win11 is now.
I used XP until Windows 8 was released. At least I got a cheap Windows 8 key from Microsoft back then. And upgraded to 8.1 and later to 10. So I got my money's worth out of it.
Such a shame things will never be as good as they were again.
2005 was a different story, one the opposite of this one.
While Vista didn't have high specified requirements, it gobbled resources so updating from XP to Vista you'd have a noticable slowdown.
Win11 is the opposite of that story. While modern PC models (as in 5-year-old when Win11 first came out) can run Win11 fine, Microsoft forces requirements which aren't needed.
Sure, while having a better TPM and newer processor is a good thing, making anything other than that ewaste (because windows runs 90+% of consumer PCs, with Apple being the majority of the 10%) definitely isn't.
Vista was absolutely the slowest thing imaginable. They reduced the requirements as part of a marketing campaign for "Vista-ready" PCs, but PCs that ran it "well" were few and far between. Even after 7 came out if you went back to Vista it was noticeably slower.
The minimum specs seem to be an 800Mhz system with 512MB memory. No, Vista will not run good on that. Even Windows 7 will not like it.
Windows XP with SP3 will run on that, but even that will feel sluggish on 800Mhz.
That's like early XP computers being released with 64 or 128 Megs of RAM. That may be the minimum specs but it's not gonna be usable.