> Chasing enemies is much more annoying than them coming to you, so that would be a punishment to the player.

It seems I've failed to express myself clearly. The idea was that at some point, "low-level" adversaries simply stand no chance against a "high-level" PC, which should be obvious to both sides -- so acting accordingly on both sides would make sense without taking the fun out of the game, because -- and hear me out -- at that point in the game, chasing the low-level minions should be the last mechanic the player is forced to endure. When you are going for a dragon, you should not be forced to stomp your way past overly self-confident "newts" or mow down swarms of goblin youngsters…

Naturally, if the PC chooses to chase minions fleeing in terror after they took out the most courageous (or silly) third of their clan, that should be an option… and arguably it could even bring some satisfaction after the PC's low-level struggles, perhaps. But should this be the main mechanic? Definitely not -- at least not in the kind of game my thought experiment addressed.