JUst to add to my post above: B&W is an abstraction of reality, and is NOT the way we see things. We see in colors. B&W removes colors, and so the clues and cues the eye and brain get from B&W images are different that they are for full-color images. Artistic intent would dictate how a scene should be rendered; different image manipulation methods, like burning-in of highlights, dodging or bleaching of shadow areas, and intensifications or moderation of mid-tone tonal values, and the degree of contrast in the highlight, shadows,and mid-tones--ALL OF THAT stuff, determines how an image looks, and influences how it is seen or interpreted by the viewer.
There is no one, best way to render an image in B&W...a light,ethereal,early-morning marine scene with a rowboat and a foggy lake setting might have almost ZERO pure black tones. The same scene, shown at 4:30 PM on a sunny October afternoon might be best rendered with a very deep,charcoal-gray sky to represent the bright, deep blue sky of a sunny fall day, and might have brilliant,specular highlights on the water, and crisp, high-contrast mid-tones, and deep, dark, yet still-detailed lower tonal values.
Also, high-contrast images can convey abstraction, or show design elements like lines or repeating shapes. Low-contrast images can convey serenity, tranquility,or darkness or dim lighting. There really is no one pat answer as to how much contrast,either local, or overall, is best, because it's highly subjective,and varies from photo to photo. It is possible to take the same negative, or RAW file, or scan, and create two wildly different images, simply by altering the contrast significantly.