T-Rex: One day the ability to travel BETWEEN timelines is invented! If you don't like an event that happened here...

T-Rex: ...switch to a timeline where it didn't happen!

T-Rex: Of course, the second this happened people started switching timelines like crazy. Spill coffee all over your new couch? NEW TIMELINE. The slow decline of democracies in the face of populism? NEW TIMELINE. Ask someone out and they said no and now you're too embarrassed to see them again?
Dromiceiomimus: New timeline?
T-Rex: NEW TIMELINE.

Utahraptor: What about if I'm the guy with the couch?
T-Rex: Huh?

Utahraptor: What about if I'm the guy who DIDN'T spill coffee on my couch, and then another me shows up and is like "this is my couch now"? I don't want that clumsy oaf on the couch! He's already spilled coffee on it once!
T-Rex: Oh, you just move to a timeline where he didn't show up.

T-Rex: In conclusion, this causes a cascade of timeline refugees, but on the plus side really unpopular timelines are almost empty, so that's nice.
Off panel: Does this story have a moral?
T-Rex: My friend!
T-Rex: Not in this timeline!!