The issue is uniqueness. If you can replicate a building exactly as it was 100 years ago, then the original one has no particular value. To make sure to disting

The issue is uniqueness. If you can replicate a building exactly as it was 100 years ago, then the original one has no particular value. To make sure to distinguish the original one from a copy, people add value to its uniqueness by saying it can't be replicated 100%. When I visited Pompeii, I would have loved to see the city rebuilt as how it was originally. They have pictures here and there displaying how the city could have been but I think that the immersiveness would have been much greater if it looked as it was previously.