I’m afraid there’s a flaw in your reasoning. You say we can ditch the question of life’s meaning along with theism.

Fine, but you also say, “Humans created gods thousands of years ago, then used those gods to give ourselves a purpose: to worship the very gods we had created. Life here on Earth seemed cruel, capricious, and difficult, but there was meaning behind it all. Death wasn’t the end.”

There you’re implying that the question of life’s meaning came first, and that that question motivated theism. We created the gods to give life a grand purpose. Now that the gods are dead, life lacks a cosmic purpose, but the desire for such a meaning remains because it evidently preceded religion.

What’s the basis of that question of life’s meaning? I think it’s clearly related to our freedom which animals lack. The freer an animal is, the more it understands the world, and the longer its genetic leash, as it were, the more the more animal will wonder whether its self-selected functions suffice because this animal will have been liberated, to some extent, from its evolutionary life cycle.

Thus, existential philosophers emphasize the question of life’s meaning because they take our autonomy to be fundamental to the human condition. It’s that freedom we found ourselves with even in prehistory—after we became behaviourally modern persons (as opposed to animals) but before organized religion—that prompted the question of life’s ultimate purpose. What’s the point of being free if we don’t really know what we’re doing in life and can only speculate, pretend, or mislead each other and ourselves, as we typically do? Is godless life just a farce? Are we the butt of a cosmic joke?