The Buhari administration came in unprepared to deal with the situation of being between a rock and a hard place. On one side freeing up exchange rates would have most definitely caused a widespread collapse of the banking sector, elite businesses reliant on an overvalued exchange rate, the cost of homes and children in schools abroad. On the other hand not freeing the exchange rate would have led to a recession as private sector investment retreated and sat on the side lines. They chose the latter option and threw the Nigerian masses under the bus to safeguard the elite and politically connected.
Unfortunately, the Buhari administration does not understand that at least 4% of the magical 6% growth Nigeria attained between 2001–2014 came from private sector investment and once investment is lost it takes time to regain confidence (as the US 8 year stagnation showed) which is why the Nigerian economy by focusing on oil revenue will remain in slow growth mode for quite a while.