Are you asking the El Salvador government to sell their Bitcoin and use the profit to invest into other cryptocurrency, that is not a wise decision for them to take and it's going to be a wrong decision by the government because then they'll be taking on more risk than when they invested into Bitcoin. A decision that they can take and they'll have a valid reason why I'll support them to sell is when the government wants to invest the profits that they have made into other things that'll make the economy of the country to improve. A governments should improve the economical condition of his country hence using money to invest into factory that'll provide job for the citizens is better than just having profits stored up from Bitcoin that isn't being used to better the standard of living of the citizens.