According to Statcounter, Windows 11 held a 55.18% market share in October 2025. That share dropped to 53.7% in November and dropped again in December. Now, Windows 11 holds a 50.73% market share.
https://gs.statcounter.com/os-version-market-share/windows/desktop/worldwide
Many are rollback to Windows 10, but Linux is increasing as well.
https://gs.statcounter.com/os-market-share/desktop/worldwide
Statcounter is running on more than a million websites. They track user metadata across these websites.
While this doesn’t give you absolute numbers for everything, it should be enough to notice trends.
Their methodology is on their website.