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)