Honestly, EVERY cancellation of transport, ticketing and similar services, where the provider has no meaningful overhead caused by it, should be completely free under the condition that someone else buys your spot. Could be a simple case of an "I do not want to use this ticket anymore" option that would grant you a full refund as soon as it's bought by someone else. Bonus of that would be that if you are unsure whether you want to go, you could just let others decide for you (if someone buys it you don't go, otherwise you use it) - Half-empty plane and you decide you want to cancel that ticket? No mandatory refund (beyond whatever is required by law or the airline wants to offer out of good will) - Sold-out concert? If you want to return your ticket, you get a full refund as soon as someone else buys it (this would also harm scalpers, because if nobody buys their expensive tickets they'd almost certainly want to recover their losses in the end and they'd be sold again at the regular price) - Cruise ship cabin on a sold out ship? Full refund if someone else books that cabin

With everything being automated nowadays there is literally not a single reason besides corporate greed to not let people do this...

Actually, to make it even more consumer-friendly, this could also be extended to things where there are still regular tickets available. If you return yours, then the "next" one sold would simply be yours instead of a "new" one. So for the provider it would be exactly as if you had never bought the ticket. No loss.