On the occasion when my alarm goes off on my pixel and I am not in a position to just swipe it away it helpful says just say stop to stop the alarm, but infuriatingly struggles to respond. I believe this relates to it not opening the Bluetooth headphone microphone and listening for the command and switching off the phone's microphone because Bluetooth headphones are connected.
I feel that people at Google must not be using pixels because lots of this stuff really should have been fixed years ago.