A very relevant article here from the UK perspective
Drones involved in near misses at UK airports - BBC News
Hmmm...
So we have two airliners - one at 2,000 feet and the other at 4,000 feet "during take off". I'll defer to the bus-drivers on here, but would I be right in thinking that ya typical aerobus will be doing well over 200mph in that phase of flight? Let's call it 100m/sec.
To see an object and explicitly identify it as a "drone" you'd need to be within, what, 200m of it? Now I know airline pilots are living gods with all the omnipotence and omniscience that goes with it, and call me a cynic if you wish, but I have real trouble believing that in the two seconds between initial visibility and passing "within feet" even an airline pilot couldn't accurately identify the object which he/she believes went past the window. It could just have easily been a bird, a party balloon or the consequences of last night's crew-party in the hotel.
Once upon a time it was UFOs - now to pilots everything is a drone. Tell you what - fit a dashcam and let us all see what bit of airborne flotsam you're calling a drone this week...
PDR