Wonders of the World

Does anybody feel like it's confusing nowadays to at least say 3 wonders of the world? The List of Wonders of the world has been changed so many times since the ancient time. It's confusing you know, why change the list? You can add the new one to the old one, but don't remove the old one just because the new one's cooler. Okay so based on so many sources, here are the Wonders of the World:

The old version (Only 7):

1. The Giza Pyramid
2. The Eiffel Tower
3. Borobudur Temple
4. Taj Mahal
5. The Great Wall of China
6. The Colosseum
7. Pisa Tower

And then comes the newer one, but still considered as the old version (it became 8):

1. The Giza Pyramid
2. The Eiffel Tower
3. Borobudur Temple
4. Taj Mahal
5. The Great Wall of China
6. The Colosseum
7. Pisa Tower
8. Mekkah

And then it's changed into this one (2016):

1. The Great Wall of China
2. Taj Mahal
3. Machu Pichu
4. Christ the Redeemer
5. The Colosseum
6. Chichen Itza
7. The Giza Pyramid
8. Petra
9. The Stone Henge

But, based on Wikipedia, there's the list of the ancient world's 7 wonders here are the places:

1. The Great Pyramid of Giza
2. Hanging Garden of Babylon
3. Statue of Zeus at Olympia
4. Temple of Artemis
5. Mausoleum at Halicarnassus
6. Colossus of Rhodes
7. Lighthouse of Alexandria

I think all those places above are all the wonders of the world. Why are the called as "wonder of the world"? because nowadays' people are wondering how they all are built back then. There were no cranes, trucks, cars, tractors, or even calculator to calculate stuffs. And people back then could build all those structures well and still exist until today. I wonder what if 100 years from now people will also wonder "Omg, how did they build Disney Land or Taipei 101? They didn't even have flying cars back then!". My question is, are we getting more stupid, or is it just those ancient people were as smart as hell? I don't know. Maybe there are futuristic people from the future who traveled back in time and helped the ancient people? who knows? Or maybe even crazier, maybe we are the ancient people and they are the futuristic people? What if it's like that? Conspiracy theory mode: on.