The gold monetary system of past did not fail by fundamental design. Central bankers first perverted it with paper notes and leveraged markets. Finally, in 1971, government abandoned it due to their own overspending. The resulting fiat we have today will fail by design, it never had a chance. Money cannot be baseless and printed into infinity. Having a central authority issue money at will results in corruption, class disparity, and eventual hyperinflation. All of which progresses slowly and inconspicuously at first.
The selling of US treasuries has been wildly popular and widely reported. China has been a seller for 3 months now. Japan has flipped to selling in August, now having the lowest amount since 2011. It should be of no surprise that Russia finally has no US treasuries, having sold off their remaining holdings as of August. Russia chooses to invest in gold instead. They are not alone, many countries are. Including most recently Poland and Hungry. Hungry has increased their domestic gold reserves ten-fold, to 31.5 tonnes in just the two weeks starting October 2018!