Conversely, I have Windows 10 running quite well on low-spec (for the time, not just for now) 6GB Acer laptop that I got when Windows 8 (not 8.1) was current, that went through in-place upgrades to 8.1 and then 10, and it's got a ludicrous amount of cruft that I keep meaning to clean up.

So, while I don't doubt your story, I can't help thinking that it may not represent the general experience.(Maybe I'm just lucky, though.)