[FinnKuhn]

I think the issue is response time.

Once a drone has been spotted notifying the correct person and getting the drone started would take a few minutes I assume.

Furthermore you can't really deploy a drone at an airport while it is still active, which is the reason they are banned from operating there in the first place.

[jiehong]

I was about to counter your first part with automatic detection and drone launching, but your second point makes sense.

[FinnKuhn]

From the other comments I believe that tracking to identify the operator and launch site together with automated targetted jamming are the most effective solution. I don't know if such a system exists already and if it is quick enough to react without interferring with airport operations.