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
You can install League of Legends on Linux using Wine and Lutris: link
Unless they’ve completely changed the way Vanguard anti-cheat works, it’s impossible to play even if you do manage to install it