It doesn't vibrate. It doesn't move on its own. You can't move it by hand.
And like I said, there is no play during normal riding obviously. Once the rotor has moved against a stop on the hub it won't move under normal riding conditions and normal braking force. I can however get it to move back and forth if I pull the brake and move my wheel back and forth on the ground with enough force. It is not a functional issue, I believe. But I still find it weird, coming from 6 bolt rotors on my gravel bike where this is impossible, obviously.