Gyroscope.x

The x read-only property of the Gyroscope interface returns a double precision integer containing the angular velocity of the device along the its x axis.

If a feature policy blocks use of a feature it is because your code is inconsistent with the policies set on your server. This is not something that would ever be shown to a user. The Feature-Policy HTTP header article contains implementation instructions.

let gyroscope = new Gyroscope({frequency: 60});

gyroscope.addEventListener('reading', (e) => {
  console.log(`Angular velocity along the X-axis ${gyroscope.x}`);
  console.log(`Angular velocity along the Y-axis ${gyroscope.y}`);
  console.log(`Angular velocity along the Z-axis ${gyroscope.z}`);
});
gyroscope.start();