Another -- probably lesser -- reason is the normal pendulum swing from one extreme to another that is common where fashion is concerned.
This post presents examples of overly-busy looking grilles and front end ensembles on American cars of the 1950s, an era noted for extravagant styling themes. Then recent and current examples are shown, illustrating that we now seem to be in a period even more extreme than the '50s.
The 1950s images are of cars for sale. The others are manufacturers' publicity photos.
1950s American Examples
Classic overstatement that was toned down for the next model year.
This is a modernized version of the traditional Packard grille intended to better blend with post- World War 2 styling trends. The sculpting is rather Rococo, but the overly decorated part is the "teeth" that thankfully disappeared on the 1953 facelift.
If the decorations on the face of the hood were eliminated, the design would be a lot more coherent.
A three-level grille-bumper ensemble, each level having a separate theme.
This design approaches the confusion seen in some of the recent images below.
Current and Recent Examples
A small car with intentionally funky styling.
The Nissan badge and its chrome nest serve as brand-wide identification.
Variously termed as "hourglass," "spindle," and (by me) "back-to-back Lexus Ls, this has been a Lexus theme for several years now. And, as seen farther below, Toyota seems to be adding it to its mass-market brand.
That enduring, yet somewhat inexplicable Moebius-diamond symbol reinforces an already somewhat cluttered design.
Audi pioneered the theme of draping the grille over the front bumper.
Count the textures on the face of this Genesis by Hyundai.
This car has some interesting sculpting, but it gets carried a little too far on the front end. The sweeping element atop the grille and its details do not relate well to what is below.
This design is cleaner than most shown here. But the faddish fake air intakes flanking the grille add to the clutter.
An odd, droopy look to the front.
As mentioned above, Toyota's mainline American sedan is now getting a Lexus-like frontal design. The hood face, the faux air intakes flanking the actual grille and the dark, two-level apparent grille segment do not work well together.