Now, even modern office is surprisingly fast on desktop, despite having lots more features. We can talk about performance on the desktop all day, but if you want to see the real perf regression, look at all these web apps running in the browser - they are absolute nightmares unless you happen to have a very nice machine to use them with.
I am an avid Debian user for many years, lastly I used FreeBSD for a couple of months on the x201. Now, I'm using ElementaryOS.
With Debian iwlwifi was a problem, did not work reliably. FreeBSD was a lot of hassle to work with -with no network manager being present etc.-, but driver support was excellent. ElementaryOS is currently working like a charm.
Another tip besides installing an SSD is to enable multicore support in Firefox.
Why isn't this enabled by default on detection of multiple cores?
Other versions of windows, I couldn't tell you. Have used everything from 3.11 to 10, skipping 8. Never felt the need to time them.
Sorry, as anecdatums go, I realise this one is pretty poor quality.
But in a sense you are right, Windows 10 is running very fast on the latest intel proc and SSD here. Still once in a while I get annoying slow downs and it does seem a little bit slower then what I could remember from the speed Win 3.11 was running on HDD on the Pentium I. But the programs were less featured then as well. LibreOffice Writer 5 starts in 7s on SSD here.. I thought Office97 Word was a bit faster on 98 or XP back then... but these are memories from almost 20 years ago, maybe I do see the past as to rose-colored. To test this I have to define what I exactly was comparing to what - general speed of usability or the exact same programs under different OS's with the exact same hardware. On both accounts it might very well be much faster with previous 16/32bit and less featured software.