Using a pair of Bose QuietComfort 15 headphones with my Moto Z Force Droid, the volume control has no effect. It's always the maximum volume even when the indicator is all the way to the left.
This is not an issue when using the speakerphone or with any other app.
Android 8.0.0, Phone version 10.0.0
Wired headset functionality (such as volume control during calls) is limited when it comes to phone/headset compatability. For the QuietComfort 15, those features were designed to work only with some Apple & Samsung devices when manufactured by Bose.