I, too, made this assumption. Then I learned it was an actual product my ex-employer had selected and kept using.
It still didn't make sense why an enhancement request and a fix request couldn't be moved between queues. Or why I received three (at least) emails when an issue was closed.
it's an approximation of dangerous areas, catenary curves are more accurate than straight lines but you don't know the length of the cable so you don't know the droop height.
A cage around the drone, there are kids toys like this, and also commercial products for inspection. Prevents contact with other objects, contact can be sensed and reacted to. https://www.flyability.com/elios-3
Doesn't protect against everything, like Spanish Moss which dangles from trees, but that is a lot bigger than a long thin wire.