Be careful what you wish for. With the dollar as a reserve currency, it is very difficult for the Federal Reserve to manage domestic monetary policy because the US financial system must accommodate not only conditions in the US, but also distortions introduced by the use of the US dollar as a reserve currency, and these distortions can be massive. The most obvious example is the way over the past decade systematic industrial policies mainly in China and East Asia aimed at running trade surpluses and the accumulations of reserves meant that the US economy was forced to adjust in ways that created large and serious imbalances.

For another thing, liquidity is a key requirement, and it's unlikely that the RMB will match that of the dollar.

Finally, for a currency to achieve reserve status, there must be some systematic way of delivering the currency to central banks and other players who want to acquire it, and the US does so by its ability and willingness to run persistent trade deficits and open capital accounts. How does China propose to do that?