It's invisible, therefore it has no color. -Diogenes, probably

I didn't disagree. It's just that we don't frequently encounter throwing microscopic bits of things into the air in our lives, especially early lives. It's pretty normal to be curious about the color of the sky as a child, and it is not obvious that distance of air is what makes enough of a difference. I think you've entirely missed the point of my original comment.

To understand why the sky is blue and why butterfly wings are all sorts of colors even though the material itself is not that color is not something that is intuitive or easy to understand without a great deal of experience and prior knowledge.

I came upon a silly scene,
As they opined 'bout blue,
"The lemming's comment rhymes!", I screamed
An experience quite new!