There are lots of things to worry about, The loss of the dollar’s world reserve status is not high enough on the list to be of much concern.
Central banks are run by people who have no ownership of the assets. So, their motivation is to keep their jobs and the value of their pensions. Their jobs are based on following rules set by governments. These include the following:
1. Keep interest rates low
2. Keep the currency from rising internationally
3. Keep the economy out of a recession
4. Keep the largest banks in business
5. Keep the illusion of price stability
The only tasks related to the type of reserve asset in the bank are #1 and #2. The bank must buy government IOUs: first, domestic IOUs; second, foreign IOUs.