I believe such move could support the government a lot and it can somehow stop those gambling addicts also who spend a lot of money and time on gambling. It's surely going to be a positive move for the economy.
Not sure if it will make a difference though, unless they are going to rake like half a billion a year from gambling taxes. They are so deep in loans already and perhaps this is the reason why they want to leverage taxes on gambling.
But there is great concern about corruption, yes it's happening everywhere, but countries like Nigeria and other 3rd world countries are susceptible and so hopefully strict implementation is needed by the Nigerian government so that their taxes from gambling will not be cut in halves.