I wish they made it so fighters can shoot them down. People put them in places I can't reach with an Apollo but still gives them some useful vision and there is nothing I can do about it.
Sometimes when killing the drone the units will stop firing after a time so I assume it is dead and not giving any intel, but the drone is still physically there, so I'd say that is a bug.
Tbh I think they are a little too hard to see. They do give off a radar signal but if they are in your base or around a node in your vision. then they are very easy to miss.