Reconnaissance aircraft are notoriously difficult to hit, due to their high altitude and high speed.
I mean, maybe in the 80’s? The technological advancements of SAM have basically made speed and altitude mean next to nothing. Now most things depend on being hard to pick up on radar, or like the plane in the article, are just large planes filled with electronic warfare equipment.
Firing a bunch of ordinance into the sky would just mean raining it back down on your own population.