Here's a thought experiment: if you are able to see a the still mostly full moon tonight, and luckier still if you can actually see some stars, when you look at the moon, consider that you are actually looking down at it. You, as a person are hanging over it sort of perpendicularly to the surface of this sphere. Keep your eyes on it long enough that you see it move just so imperceptibly slowly, until you feel a bit dizzy or get a bit of vertigo from the motion. From this vantage point of hanging off the side of a sphere, it's like seeing the moon for the first time, and once you have seen the movement you will recognize in that moment that you are _on_ a planet, which is suddenly finite with an obvious curvature, and the most immediate question is, what the hell is this thing and how is it possible we can distract ourselves from contemplating it?
It is the literal definition of physical perspective, where when you view the moon as downward from you, it makes everything here seem both finite and possible. The stars when you look down or out at them become asymptotic points on a blanket-like manifold. The mistake was that we think these things were merely "up," and things "down" here are the sum of the real. I think when you see how we are situated relative to the moon, other planets, and stars without the narrative filter of a self that looks inward, it's not that nothing matters, it's that anything that obfuscates this sense of clarity you can get about our place in the cosmos just from looking down the hollow space between us and the moon - is necessarily absurd.