Lag depends not only on Internet connection and distance to Lichess, but also on Windows settings. Before applying these settings, my lag was 210ms. After I applied them, it became 95ms.
This is important. Lichess lag page may show that your connection is fine, but Windows may still add 100 or more milliseconds to your latency.
This page shows how to make your connection much faster.
Restart your computer after you apply these changes.