Believe me, this is not about any form of adoption from the Nigeria government, this is for their own selfish gains, since they can't control people not to invest in crypto they have to find ways to make gains out of crypto adopters, now that sounds more like the Nigeria government.
I wouldn't call them selfish I think they see that the people of their country are using Bitcoin or cryptocurrency even when it was illegal, Country and government both ain't get any benefit from this, so by imposing taxes, at least some money will be deposited in the country's reserves. I applaud their step. I think it will not only increase the use of cryptocurrency in their country but also increase the users and also increase their country's reserves through this step