It's not technically correct, it's blatant historicism. There has to be a physical cause for the fence. If whoever put up the fence decided that it wasn't important to list the cause then their fence was ill-conceived from the start.
In some cases the fact that an object survived for so long might make it unique and worth study, but a million little (usually unenforced) regulations left around like so much garbage should be swept up.
In some cases the fact that an object survived for so long might make it unique and worth study, but a million little (usually unenforced) regulations left around like so much garbage should be swept up.