>>7785052 (OP)
At least show art by the most famous Spider-Man artist, John Romita. Anyway, you are missing the historical context: comics during the "golden age" and "silver age" were printed on cheap newsprint. The art was also reproduced at a smaller size than the original. The style of drawing with a brush and laying in large areas of black with "feathering" (hatching done with a brush in which the lines go from thick to thin) was adapted to these constraints. The printer's ink would bleed slightly on the newsprint. Very fine lines and details would not reproduce well. You also have to keep in mind that those artists and their readers would have grown up watching black-and-white movies and TV shows in which this kind of shadowing was used for both aesthetic and practical reasons. Comics were cheap entertainment for kids that had to be produced quickly. That said, some of the artists in those early days were really outstanding. The style became associated with the comics, and evolved somewhat over time. Sadly, there aren't many comic book artists today who compare favorably to the greats of the past. Digital coloring is hideous, and digital inking tends to look harsh in a way that trad doesn't, but it's also just a question of drawing ability. Comics, like illustration more generally, had their heyday and then fell into decline. Whether the art falling off was a cause or an effect of that, I'm not sure.