> There are quite a few machines connected to the internet right now with no owner. Boxes forgotten over time and power consumption not enough to matter.

They are on somebody's land, and unless they run completely off of solar or turbine then they are still drawing someone's electricity. Their access to the internet also must be mediated through a SIM card or a wire to someone's network. With no dispute from other possible owners, the owner of the related land, electricity, and network access (far and away these will all be the same party) is the owner of the internet-connected device.

Sure it's a social construct, but billions have killed or been killed for money, land, and ownership of assets. Social constructions at their extreme are just abstractions of power which determines life and death. Something being a social construct does not make it invalid or ignorable. All of life is a series of intrapersonal relationships built atop social constructions. I'm sorry but I find pointing out something being a social construct only serves a somewhat naive/juvenile purpose as an easy way to make a statement look nonsensical.