You have a valid point but the article is about co-working spaces, not open-plan offices.
It's my desk and my Ethernet cable and it's plugged into my laptop. No one else sits at my desk and no one should unplug my Ethernet cable from my laptop when I step out of the office. Period.
Edit: So is an office with three desks (one desk assigned to each worker) an "open-plan" or a "shared working space"? Three people work in that office and they all have a key to the door.
If none of this is true, you might as well be talking about purple dogs stealing the umbrellas from your hamburger patch.