For #2, how do you avoid recording all the things people around you are saying throughout the day? Custom microphone to minimise picking up surrounding sounds?

For #2, how do you avoid recording all the things people around you are saying throughout the day? Custom microphone to minimise picking up surrounding sounds? Some kind of speaker recognition to identify and isolate your own voice (does that work when you have a cold)? And if you're not avoiding recording other people, how do you succinctly notify everyone in capture range that you are recording them? This seems problematic from a standpoint of social norms and etiquette. In public/shared space contexts people know they can be heard by bystanders, but that is very different from being recorded and having your utterances indexed for later retrieval.