An example would be a version of the trolley problem where you can either allow the track to remain on its current path which is empty, or divert it to harm an individual unnecessarily. This is a choice between a universally good outcome or a universally bad outcome.
Whereas the typical trolley problem is an ethical dilemma since both options are harmful and neither are ideal so it’s choosing between 2 bad outcomes.
I like this one the best. A dilemma is not necessarily that there’s no good options, but rather the decision is difficult. Think of the time traveler killing Hitler problem: if you kill Hitler too early, he isn’t globally hated anymore when time plays out, and you’re just a murderer. Too late, and you’ve allowed so many people to die just to justify that he deserves to die… Where’s the ‘right time?’ There’s a giant spectra of time that you can make as a justification of when to kill Hitler.
To quote myself, there’s no “ethical certainty” when (hypothetically) travelling back in time. You can never know the untold devastation you will introduce or avoid by making major or even minor changes.
I love time travel stories but most of them really skip over some of the more complex issues.
Which reminds me of a fairly low budget movie that was actually not bad, Time Trap. Check it out if you can find it.