Have we become such a wasteful society, that we just throw working things away, because there is something new?
My 2010 notebook is still more than fast enough for Windows 10 (a bit slower at the moment than it was under Windows 8, but that is probably down to re-indexing). We have moved towards more mobile and more energy saving hardware over the last couple of years, so the bar for the operating system resources has come down, not gone up, so it isn't a wonder that many older PCs, especially high-end when they were bought, are still doing their job.