It assumes that the offending "drones" are from a specific manufacturer or range of manufacturers so they can guess the control achitecture and the GUID of the C2 link (2.4GHz spread-spectrum FHSS pseudo-random channel-hopping). Most of the "offending" drones are built from sets of components and have software that's easily made imune to this kind of attack. WIthin days of this kind of device being deployed there would be hacks available on the interwebs to update the on-board software and make even the standard ones imune as well.
Conclusion:
The Register uses journalists who are just as utterly clueless on technical issues as most of the rst of the media, so they are [again] just embarrassing themselves.
PDR