I think they could find plenty of balcony railing designs that are safer that you would find to be appealing enough that it wouldn't bother you.
This one is five feet: and when you elevate it and add something in top (to make it less likely someone would try to go over) it reaches six feet. It isn't like an open view but it is pleasant looking. If you make it tall enough that no one could squeeze over the top I don;t think this would be that bad (It might even make a ship look more interesting from the outside, instead of like modern Portuguese apartment buildings.
But what you really need is something people cannot climb over and has barbs at the top: