It's named after the main adventuring guild in the world, the Pathfinder Society. Which is also the name of Paizo's irl community

A "Pathfinder" isn't just hiking. It's a person who goes first into the unknown to make the path so others may follow. It's a name for an adventurer/traveler or another way to say "Trailblazer".

To be fair, there’s a lot of people arguing for D&D to be about Dungeons and Dragons. That implies that lots of people play it without neither Dungeons nor Dragons.

You can’t be serious, right?