The intent of limiting "copying" is that it protects the incentive of people to create, and through creation, progress of "science and useful arts." This video takes an overly simplified view of intellectual property. Imagine you spend a decade researching and developing a new tech product; as soon as it's to market everyone gets to copy it and, at least from a financial standpoint, you get nothing. That means most of the advancement will be left to those who already have the times and means to be scientific dilettantes, like the 18th and 19th centuries.