According to AppleVis userBrian Negus, “…Siri is now less flexible about how commands are formulated.
I used to be able to say just ‘do not disturb.’
This no longer works, and Siri now requires something like ‘turn on do not disturb.'”
Apple
It’s possible some of these removed commands may still be present, but require more specific wording.
But it currently appears as though they’ve been entirely removed in this case.
Regardless, manually setting up custom commands to restore previously available functions isn’t ideal.
Apple
