Not quite sure what you're saying? The Mint stopped using 92.5% silver from 1920 as the price of silver during WW1 had risen to the point where it exceeded the face value of the coins being struck. Yes, it came down again a few years later, but the Mint were never going to reverse their decision. The same thing happened after WW2 when silver was abandoned altogether but this time it never came down to make using it for coins cost-effective.
I'd treat YouTube videos with a large pinch of salt!