Light theoretically would travel at c in a vacuum, but I think a vacuum is practically impossible. So light doesn’t ever travel at lightspeed? And therefore it does “experience” a tiny amount of time between emission and absorption/reflection?
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No, light always moves at `c`. But it may not move in a straight line.
When the light moves in some material, it has to avoid atoms, so it moves in zigzag pattern, making the total path longer. So it appears that light moves slower, while in actuality it does not.
You may ask: “if the light moves in zigzags, why doesn’t it scatter in all directions?” That’s because of a quantum mechanics. In quantum mechanics, light moves in all possible paths simultaneously, but two paths can also cancel each other.
In transparent materials, all scattering paths cancel each other, only those who return on the refraction line don’t. In other materials, the light does scatter. The exact behavior depends on the placement of atoms relative to each other.
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