No Light — No Color!
This resource pack makes blocks smoothly become less colorful when they have less block light. Sky light doesn't affect this, only block light. Please note — this resource pack applies only to most of the blocks. Entities, some block entities, particles and other stuff will not be affected due to a different lighting method. Maybe I'll try to make entities and block entities work in the future.
Versions: 1.17 — 1.21.3+
Doesn't require Optifine, and works with it too.
Does NOT work with Sodium.
Customization
You can also adjust radius and smoothness of how light will colorize blocks.
Go into the resource pack into a file assets/minecraft/shaders/include/no_light_no_color.glsl
. You can change the numbers in the first 2 lines. The variables don't work very intuitively so just play around until you are comfortable with the result.