Yeah, spill is never relevant to seeing at long range, because its just the unfocused light that "spilled out" right in front of you because it missed being collimated, etc.
Spill is a curse in some uses, and a practical solution in others.
For some tactical scenarios, spill is cursed as it may illuminate your position/your buddies positions next to you to an opposing threat, etc.
For for long range illumination, too much foreground brightness can hurt your ability to open the pupils wide enough to make out dim distant targets.
For most other scenarios, the spill can sometimes be adequate to see where you're going, as the ground in front of you will have at least some light on it even though the beam itself might be aimed off at the horizon, up into the trees, etc.
The focused part of the beam typically has a hot spot, where the light is mostly tightly focused...and, that is what is able to reach the longest range.
The corona is the focused part of the beam that is not as tightly focused as the hot spot itself...a softer ring of light, like a donut, that surrounds the hot spot. This part of the beam can illuminate targets up to a certain range along with the hot spot, but, it falls off as range increases, so that eventually, only the light from the hot spot is illuminating distant targets. The corona makes the circle of light larger and more useful at intermediate ranges.