The last speech by the CBN proves they know nothing about cryptocurrency.
With what I have read about all what CBN has been saying about cryptocurrencies, from the first to the last words, most are not correct, that is why I even make some comments that CBN are full of false information. Cryptocurrencies used in money laundering, is fiat notore used than cryptocurrencies. Cryptocurrencies used in terrorism financing, are Boko Haram using cryptocurrencies? I doubt that because fiats are used, I believe some people thinking to be good are sponsoring Boko Haram with fiat. Also cryptocurrencies transactions are anonymous, that is what CBN presedent said that make me conclude that this man is either not exposed or just passionately hate cryptocurrencies as banks from developing countries do.
Talking about what to mine, I'm also of the opinion that mining bitcoin now might not be a really good idea especially for an individual miner. smaller altcoins with more rewards and some minor difficulty should do just fine but new projects often focus on POS staking instead of good ol' mining like in the early days.
Not that mining bitcoin is not profitable, but require more powerful miners to do. To go cheaper, it is better to mine with altcoins with graphics cards that altcoins can be mined with. But, with good and cheap electricity and capability to buy powerful ASICs needed, you can also mine Bitcoin profitably in Nigeria, provided electricity is constant and cheap.
I do not know of altcoin, but I know some sites that can easily help in calculating bitcoin profit for ease which I think can be helpful
https://www.buybitcoinworldwide.com/mining/calculator/https://www.cryptocompare.com/mining/calculator/btc?HashingPower=40&HashingUnit=TH%2Fs&PowerConsumption=1500&CostPerkWh=0.12&MiningPoolFee=1