In some instances, the natural substances are preferable because they come with multiple components that work better together than in isolation.
Too bad that only works for food and fruits.
As you said, herbs are all or nothing and dosage is inherently unreliable, making the products of Western scientific tradition essentially superior for their stated purpose. On the other hand, I can't help thinking of some other products that became harmful superstimuli by being extracted in isolation and enhanced in concentration. Stuff like sugar (eating sugar cane? pretty much okay, great tropical snack. Eating cubes/spoonfuls of sugar? Terrible idea. Chewing the coca leaf? Nice little stimulant no worse than coffee. Chewing on cocaine? Catastrophic.)
It's a complex subject but in the end, I suspect it is difficult to argue with the efficacy, reliability and predictability of pills.
Oh yeah, pumpernickel has to the best of my knowledge no medicinal properties whatsoever.