The lightest colored oils I have seen have been GTX and Valvo white bottle 5W-20s.
Yes, I have visited both the thin and the thick dark sides.
Oil is like beer.
Tasteless beers are usually very light in color.
Robust beers, which any real man would prefer, are as dark as cola, like Guiness Stout.
M1 15W-50 is pretty dark, as is any 15W-40, which is why any real man prefers them.
More robust, more to savor for the engine
Oils should therefore be selected for how dark they are when new.
I wonder whether we can expect a bock oil in the fall?