If you want security through obscurity you can revert to IPoAC (RFC 1149).
replySpeech capable avians can spontaneously leak secrets
reply> probably an unsolvable category of bug as long as notifications need to show readable text somewhere.
replyLet screens always show garbled pixel vomit, decoded on device only by your private AR glasses
threat model just shifts to whoever has a camera pointed at your face, but probably still an improvement.
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