Actually, HDMI has DRM built in, and many DRM-laden apps won't work unless the HDMI DRM is working. The Amazon app has been telling me recently that my connection to my TV doesn't have it, but it actually does. Then I'll hit "play" again and it'll work. (I think it was a bug in their app, because it stopped again.)
So recording it requires something that implements that HDMI DRM scheme, but still allows you to record.
So recording it requires something that implements that HDMI DRM scheme, but still allows you to record.