@c_ratcliffe

I've never seen or even heard of drone billboards. Sounds like a modern version of skywriting. When skywriting was used in the past, it was not viewed as intrusive. But flying billboards, that sounds like it would leave people with a negative impression toward the sponsor. This is similar to ideas about using lasers to project ads onto the moon.

These sorts of things are more about the use of a common resource than about the technology itself. Airspace, especially in a densely populated area, is a scarce common resource so it needs to managed so everyone can use it fairly.