In my experience, it is. My podcast app of choice doesn’t have that permission (I don’t even think it asked for it), but it has the ability to bring up the system audio output selector widget and do AirPlay.
If anything, I usually see this for apps that want to do playback via Chromecast/Miracast. The well-behaved apps wait until the user interacts with Chromecast output, the iffier ones ask on first launch.