Chi is related, but not precisely the same thing as the scientific concept of energy. Science emphasizes objective measurement and bypasses personal observation as much as possible. Whereas scientific measurement of energy isn’t possible.
When you place your attention somewhere in your body, you can feel that it’s not just your perception that is focused there. Something else is happening. Energy is displaced to that area. It is possible to measure this: the temperature of the spot you focus your attention on will rise.
The fact that knowledge of energy seems to have developed mostly in the distant past, is related to what people pay attention to. In the modern world, we have all kinds of things that grab our attention, like TV and other media, the thousands of objects in our houses or at work, and advertising. As people didn’t have all these diversions in the ancient world, they were able to pay more attention to their bodies and feelings, so were better able to notice energy. The meditation techniques that were developed also opened the way to a precise awareness of energies.