I’m trying to get you to stop preconceiving as to what the ancients knew or didn’t know. I’m doing that by trying to get you to stop preconceiving ‘air’. Stop conceiving of air at all. Just sense it with your physical senses.
So, First of all, surely you can feel the air on your skin as the breeze blows?!?
Is it invisible on your skin? Yes, it is invisible on your skin. It also is invisible around you in a room. But if you can sense it despite its being ‘invisible’, then surely so could humans who lived two + thousand years ago???
Second, you just now claimed that, since that sensible air is invisible, it has nothing to do with how we can see any color of fading effect on distant objects.
So which is it? Is that sensible-yet-‘invisible’ air something about which the ancients could not have known? Or, instead, according to you, did they know of it only within the kinds of perceptions of the sky that brains like yours have of the sky?
So, in answer to your own most pointed question: No, I do not perceive that the clear blue sky is a solid opaque dome. I perceive only that that blue is a vast depth of blue, not a flat surface far up there.
I see its depth in a way that is somewhat comparable to the curious ‘depth’ of color of certain biological colors, such as that of many kinds of bright flowers, or of the brightly colored wings of a butterfly. But as far as I can see, the blue sky actually is deep.
In very fact, some person in your anti-YEC camp have claimed that the ancients though that the blueness of the sky meant that it was deep water up there. I can understand their claiming this, except that that blue seems to me to become clear (at night) when too little light is shown through it.