Seriously people, use the fucking fan. It clears away odors and covers up the sounds of your dropping a deuce. If you want to stew in your shit smell and revel in the music of your magical poop plops, do so in the comfort of your own home. If you’re a guest and the bathroom has a fan, turn it on. We don’t want to share.
I mean, you can stick a light switch with a motion sensor on it that’ll flip on automatically.
https://www.amazon.com/motion-sensor-light-switches/s?k=motion+sensor+light+switches
Probably easier to make your machine do what you want than it is to make global human behavior be what you want.
Its global human behavior to share your shit smells with the group?
Probably easier to just not invite shit-sharing assholes.