So if you want to keep people occupied for a looooong time without running out of game-world, focus on PvP

Or invest in "procedural content generation", where the game world is constantly generated or regenerated. The "roguelike" genre has made games that have been played for decades (like Rogue, Nethack, ADOM) and continues to grow (Ultima Ratio Regum, Dwarf Fortress). It's hybridizing into other genres like action platformers (Rogue Legacy, Spelunky, Risk of Rain). Games are creating new genres by starting with PCG (FTL, Minecraft). Civilization and the Maxis Sim games are classics in large part because of content generation.

For another perspective, game designer Dan Cook has written several blog posts on PCG leading to better-designed game systems than handcrafted content. Similarly, Jonathan Blow has argued extensively against games that extend their use of systems (eg. across all the levels of a Super Mario, Modern Warfare, or Call of Duty game, the player will see few or no changes in rules, just new sets) rather than exploring a system once thoroughly (Braid, The Witness, Portal, Polarity).

I'll leave the comparisons to "Scientific Progress [as] the PvE of real life" for the simulationists and solipsists. But I've always seen the human obsession with status and gossip as a bug rather than a feature and endeavored to advance more interesting things in the world.