Hello and thanks for your note. The use case I have in mind is while listening to music (including while driving) I don't want to be interrupted by notifications, except certain high priority ones. So I like to set to DND during these times, and connecting to a Bluetooth device like my headphones or car would be the perfect trigger.
https://mail.google.com/mail/ca/u/0/#label/%40darken.eu%2Fsupport/FMfcgxwChmRZGGnXCLCGvfXRKxzVFpsw