The concept was known but far fewer people had been exposed to those ideas and thought in those terms. That you think it is so obvious or that math as complex as geometric compounding is so obvious to you would be the actual big reveal.

On prices, the really interesting thing is not that prices are higher but that what things are expensive and what thing are cheap has radically changed. Basic food and clothing is dramatically more affordable. Anything involving human craftsmanship is much more expensive. What os available for sale would absolutely boggle the mind. Not only did a huge amount of it not exist in the past but, only a long could even contemplate buying most of what did exist—at any price. Food is a great example. Empires rose and fell pursuing or exploiting the riches of fruit and spices I can buy for the change in my pocket from any of a half dozen merchants within a couple miles of me competing for the privilege.

The fact that I can buy anything not only by waiting a piece of plastic at time but also the magic brick in my pocket ( phone ) might intrigue them as well. Basically, not matter what wonder you go to show, the real magic might be something so basic to our everyday that you did not even consider that it was required for the thing you are trying to show.

“Wait, so you guys are getting paid close to 20 times less then I was when adjusted for inflation???”