Summary
The darkness effect doesn't apply over the skies and the fog, causing the weird fog and the skies that are still bright to still appear when having a darkness effect.

Steps to Reproduce:
Find a deep dark biome and activate a shrieker or apply the darkness effect with commands. (I did /effect for this case). Stare at the skies/fog.

Expected Results
The skies and the fog darken along with the effect. Or the fog underground should simply be dark already (without any traces of sunlight) even without the darkness effect.

Actual Results
The skies and the fog does not darken like “bro it’s not even dark”, i.e. remains intact.