People, vehicles, boats I have always understood to be subject to the 500' rule. Roads, fences, water, pot buoys, I regard as not subject. It's the pilots responsibility to ensure people, vehicles, boats, and any other possible items are not present when flying low other than when taking-off or landing.
No change to Airlaw by the Judge's determination.
PS. I assume the Court was high enough for decisions to be quoted by other English courts. But even so, they would be unlikely to affect the interpretation by a Scottish Court, although Aviation is reserved to Westminster.