This is not a football match.
I have hope that this comments section will not become a sports match - all of the comments so far have been non-partisan. I guess we'll find out after lunch when the East Coast has woken up and seen this. ;)
Anyway, I don't think this shows a failure on GNU/Linux's part. I think instead it shows how far Windows has come. Go back to the Windows XP era and this situation was far reversed. XP had a poor security model and was riddled with problems. GNU/Linux has actually improved as well. It's just that Microsoft bit the bullet with Vista and went through the massive pain of re-doing much of their system from the ground up. We're now seeing the long-term benefits of that process.
And aside from changes to their security model and obvious improvements to their quality control, there's another thing MS addressed which isn't impacting those figures above but is impacting actual daily security a lot. And that is they took some of the responsibility for security back from the user and manage it themselves now. All Windows systems can have Windows Defender / SmartScreen / etc on and running and any that doesn't have Third Party anti-malware software running normally does. Windows Defender isn't fully as comprehensive as something like Trend Micro or Kapersky, but it does the job and has low-impact. The fact that modern Windows installs have proper anti-malware up to date by default now is making a big difference to the general state of end user security.