On the other side AMZN could have hired several RC plane hobbyists, fly them Emirates business class, put them into Burj Khalifa suites, fund several beefy jet, nitro or EDF planes for them (with jet getting as expensive as $5K), and have these guys on guard duty on the roof so they would take down any incoming drones (see Ukraine interceptor drones), and that would still be a pocket change compare to the datacenter damage. (of course somebody can get a startup going producing an automated container deployable unit consisting of like a 64 cell VLS with such interceptors plus radar plus optical - can be quickly deployed when necessary for example onto datacenters or say onto large ships navigating some treacherous waters )

More tech-y approach - AI (or even actual security guards) monitor the video cameras and once there are incoming drones, several MW of power can be redirected into those datacenter's large satellite dishes (more precisely - into very simple microwave generators installed on the dishes) and the dishes turned toward the incoming drones - the drones will get cooked in seconds, add the kitchen microwave sound effect.

> A few cheap drones can ...

It is temporary. The race is only starting. Soon you will have to have a hive of highly intelligent autonomous drones to have even slightest chance to make through a hive of highly intelligent autonomous interceptors, etc.

The government based defense departments are very slow and expensive though, while the extremely valuable targets like the datacenters belong to the transnationals and located across the world (and more and more in space). Thus the transnationals would have to take care of the defense of their assets themselves (or outsource it to other transnationals, like say imagine AWS providing air-defense-as-a-service), more efficiently and agile than the government defense departments. If you take a look at Palantir Karp's book "Technological Republic" you can read that between the lines there too.