Damian, one of the cool people over in the Relay FM Discord servers has created a great application that allows you to control the volume on your Mac, using your Apple Watch - WatchControl.
This is a small quality of life improvement I’ve been looking for and totally the kind of thing I can get behind. I’ve tried it, it works great and is well worth checking out.
There are two elements to the process - an app that is installed on your Watch via your iPhone, then a small menu bar companion app for macOS.
Worth a look