Sun of sand, burning in by itself does not compress tones. It simply prints the content/subject matter in the burned area of the print, darker.

The glowing look in my experience is typically caused by flare, spillover bouncing around coming from the bright areas affecting the darker areas. It reduces contrast by bringing the low tones up. It is dependent on both the tools in use (lenses, shades, studio lighting, scrims) and technique being applied (like shooting backlit vs front lit).

That glow/flare is simply a "characteristic" or "quality" of a given set of circumstances. It is neither good nor bad. Adding flare can be quite useful for certain types of photos, some portraiture for example. Reducing flare can be just as important in other shots.