The assumption is that the perp is an "eco-warrior" and the assumption is probably right. But it could have been a kid. We won't call them a terrorist because people weren't terrorised, merely annoyed.
The wonder is it hasn't been tried before. It's not that it hadn't been thought of. Airports round the world have been taking measures in anticipation. But not Gatwick, apparently. One airport- I think it was in the Netherlands- has been training up birds of prey to take drones down- an cheap and elegant way of dealing with a cheap and elegant "crime".
I put "crime" in inverted commas because our overuse of air travel is also criminal. We all know we shouldn't be pumping rubbish into the atmosphere and none of us is doing very much about it. Apart from Drone Wolf, that is. There's a long, long tradition of being annoying in a good cause. Gandhi belongs in it, so does Martin Luther King, so do Pussy Riot. They were all of them very annoying in their day and age- and look how we admire them now.