I know a lot of people who loved Windows XP, but I always hated it. Especially compared to Ubuntu, it felt like the past. Having to hunt down drivers and install them before any hardware started working was a pain, and after I tried Ubuntu and it auto-detected my wifi card and sound card, that was the end of any respect I had for Windows XP. And that's not even mentioning the number of times I had to call the phone number and read my license key to the robot to get my activation to work.
It wasn't until Vista came out before I could go back to Windows and not feel like I was taking a step backwards in time.
Well, people who like XP and older versions of Windows in general tend to like the UI, not the kernel :-P. I know many who would love a version of Windows 2000, XP or 7 (depends on the taste) with the Windows 10 kernel.
It is a problem with Windows that you have to take all of it or nothing. At least on Linux you can use whatever UI you want with the latest kernel.
It wasn't until Vista came out before I could go back to Windows and not feel like I was taking a step backwards in time.