Microsoft presented the Surface Duo about a month after Google released Android 11. However, the Surface Duo shipped several months later with Android 10. The Surface Duo has now received its first OS upgrade, but Microsoft is still keeping its first foldable smartphone stuck in the past.
https://www.notebookcheck.net/Microsoft-Surface-Duo-starts-receiving-its-first-OS-upgrade-but-it-is-another-disappointment-for-the-unloved-foldable.595279.0.html