Earlier quoted context omitted.
What would one feasibly do with this data? I guess an app could tell if someone is holding their phone in their had, and maybe put together a pedometer bases on gyroscope input. Maybe a concern if a app has access to gyro input over a period of days. But as long as it's only for actively open apps and web pages I don't really see much harm.
Facebook has a patent for using gyroscope data in conjunction with location to know who you are facing with other people around to enhance friend suggestions. You can also determine things like health and other physical characteristics, similar to gait detection.
If you do have some source of absolute orientation, like a compass, surely you just use that and don't need the gyro.