If you invested just $100 in Gold in 4000 BCE, today it would be worth $100

This is because USD didn't exist 6000 years ago, so it wouldn't be accepted as means of settlement in Ancient Egypt, thus you wouldn't find a counterparty willing to sell you gold in exchange for US currency.

6000 years is also for how long gold has been used as money. Yet, some still believe that Bitcoin is the new gold and that it will replace gold as money 😄