you can see that the blades got damaged because they're cheap plastic, perfectly fine if you just want to shoot some videos from an aerial pov. if you want to use your drone offensively you'd use a) a swarm of drones, b) a significantly stronger one or c) a swarm of hardened drones.
as the parent mentioned: the rotors become brutal weapons if you make them from carbon fiber or cheaper but still durable material
At that point why build a drone, a missile is cheaper. The terrorist > drone link is all about off the shelf components.
Military drones like the predator weigh more than a car, and we have plenty of weapons built for that. Small off the shelf drones are not something you can really hit with a missile, but you can shoot them down fairly easily with a gun. However, you don't really want to fire up into the air in the middle of a domestic city, making birds a more interesting option.
PS: They don't need to disable the drone, simply adding 8lb of weight will take most of them down easily.
You can build a great payload carbon fiber blade octocopter for $2000 or so and a few Youtube tutorials. Cheap carbon fiber blades can be $2 each! I wouldn't recommend using them if you care about safety, but on a single-flight mission they're perfectly fine. If you can get a missile (!) inside of metropolitan Paris for $2000 I would be very doubtful (as well as very concerned.)
There's also no way that a golden eagle can fly away with the drone: it'll definitely be taking it down too. A golden eagle has a payload of 900 grams. [0] Nine hundred grams! Videos of birds (typically not golden eagles) 'carrying' dogs or even goats for a half-second or so are because they perform a special swooping maneuver with their wings that lets them lift things up, taking advantage of the ground effect. There is no way this would work with a UAV, unless it was moving extremely slowly near the ground.
There are lots of people defending this PR piece because it sounds cool. This happens every time a new way to 'catch drones' comes out. Yes, golden eagles are extremely majestic. The reality however is that bullets are by far the best way to take down an unwanted UAV. Please, think about the realities of this: several hard blades going hundreds of mph is something you can only stop with a bullet. It doesn't matter if you put a super-suit on your eagles - at best, you'll just make the eagles die of internal bleeding instead.
Finally, if this UAV is flying over a city, it'll be very often above roofs/rivers/canals/etc where it's safe to crash. Give some special ops 20 minutes of training on shooting UAVs and a bullet, not a bunch of raptors that'll end up dead - that's the way to protect your city.
Area denial is a useful. Someone flying a drone at someone making a speech, a 747, or a football stadium then getting it to land in a parking lot is fine.
Anyway, you can build mortar's for under 100$. Rockets are a flexible terms, but 10 for under 20,000 is very possible. Importantly your drone needs to carry the box and what blows up where a rocket can be the box that blows up messing with your payload calculation.
PS: "Rockets red glare" refers to a mechanically simple devices that are still useful weapons.
https://www.youtube.com/watch?v=Hr-xBtVU4lg