GNU/Linux is Reaching New Highs in Turkey, GNU/Linux Up to 8%, Windows Down From 99.6% to Less Than 80%
Hyperinflation in Turkey probably helps (Apple is measured at a lot lower than GNU/Linux).
By rounding up the numbers we can say Windows was measured at 100% 15 years ago (by statCounter) and now it is below 80% (or below 20% if one also counts mobile).