The only way true isolation will emerge, is by regulatory mandate of a purpose defined hardware implementation, with a separate protocol, different datagrams (instead of TCP/IP/UDP packets) and independent land line plants, undersea cables, satellites and more.
Otherwise, you'll always have some goon plugging in a wi-fi router, rigging it to a sat phone with a modem, all just to play quake with their friends, while they idle on some crane barge, or wherever their stuck, bored on some hurry-up-and-wait project plan.
Even then, you'll still have wonder about silicon bugs, or tempest and row-hammer style attacks, for anything software ever touches, when a given industry fails to identify such threats themselves.
Otherwise, you'll always have some goon plugging in a wi-fi router, rigging it to a sat phone with a modem, all just to play quake with their friends, while they idle on some crane barge, or wherever their stuck, bored on some hurry-up-and-wait project plan.
Even then, you'll still have wonder about silicon bugs, or tempest and row-hammer style attacks, for anything software ever touches, when a given industry fails to identify such threats themselves.