What is your favorite or memorable “solution to a mundane everyday problem” that turns out to have severely dystopian implications from sci-fi?
Just finished Dream Hotel, and one of the near-future devices is an implant that allows you to sleep a full cycle in only 5 hours. Other than the “work more” implication,
spoiler
agencies use dreams as evidence against a person, and later, to implant advertisements into dreams
Which then reminded me of appetite-suppressing toothpaste from The Outer Worlds. But instead of a weight-loss product,
spoiler
it is a necessity because the entire colony is starving
(I know smartphones etc. are at this point IRL, curious about more original ideas)


One throwaway line about how the transporter works being disasembling the user (as opposed to say warping space or making the start/destination mathematically identical) lead to decades of ethical debate.