Yes, professional drones, properly licensed hobbyists for example, can fly things with a big diameter, 1 to 2 metres from tip to tip. Getting struck
in the head by a DJI Phantom is one thing, but one of these pro drones would probably slice your head off. I know them mostly from photographic /
filming services. I don't know why regular people would fly the large ones, but as they are generally modded and beefed up, it's going to appeal to
Camera crews or drones acting as a "rig" are much larger than consumer/prosumer drones. Videos of that guy riding on top of a large drone aren't far
off, especially if you're trying to fly a cinema camera. They can be modded, too, I assume, with who-knows-what battery technology (better than we get
at consumer level, I'm sure) and I think I've heard of one in the air for about 90 minutes (perhaps using 3 batteries that provide 30 mins each, with
some custom made circuitry to switch them over as they lose power, etc).
I'm not sure about the items described in the article, but I do think the parameters it mentions could quite easily describe a photographic drone or
"professional" hobbyist build of one (or surveyor drone as mentioned by icoserv though I don't know much about those). My friend had a huge one. That
doesn't right, but you know what I mean... Wingspan about the same as me holding both arms out. I use consumer drones for some filming, I fly Mavic
Pro a nice small one and I have a DJI Phantom 3 (wing span not even a full arm length) but even that I feel will knock someone out if I'm not careful
so don't really fly it
But when I've considered going "more professional" or using a service that is, there are some real beasts out there.
Hobbyists can do crazy things with whatever their hobby is... just think of the overpowered PC or car we all know that friend has, etc...
The Gatwick drones also had some curious characteristics, mostly flight time also (but no real mention of size). If you saw one of the bigger ones I
think you'd know it. That said the Gatwick incident is a messy puzzle that I think includes a lot of misidentification of other craft (planes,
helicopters etc). In England, certain laws have led (I think) to a decrease of the large drones, certainly in the hobby space (it's why my friend
previously mentioned ended up selling all of his) and is limited almost entirely now to photographic stuff as you need an enhanced operating license.
But in countries (perhaps USA) where the hobbyist drone enthusiast still has certain freedoms, they might have the capacity to pull off what's
described in the article.
Or it's aliens, that's also a valid option.