I was going to run a campaign in 5e during a primordial era, where the land is still shifting and moving. Since it takes place thousands of years before anything, I felt "adventurers" wouldn't fit the characters, and decided "pathfinders" would fit in the setting, and was a funny little tongue in cheek reference.

Since that initial idea, I've moved on to playing pf2e, and if I ever run this campaign, am definitely going to keep that name going.