There was a Supreme Court case about dual citizenship that was issued. There is some instruction on what to do when entering and leaving Ghana as well. https://thehague.mfa.gov.gh/ghana-government-directive-on-dual-nationality-and-application-for-dual-citizenship-cards-and-certificates
The Supreme Court ruled that the dual citizenship card is not mandatory, even if the executive branch had given instructions that it was. The directive above also points out the much more immediate problem for Ghanaians in countries that do not allow for dual citizenship, such as the Netherlands, where the dual citizenship card is more necessary, or the individual must apply for a visa to visit Ghana once their Ghanaian passport expires, as they could be putting their new citizenship at risk by applying for a new passport for Ghana. In that case, the dual citizen card is a life-saver (and money saver). For US/Ghana dual citizens, this is not an issue, and not letting either passport expire is a good goal.