Don't let the truth get in the way of a compelling narrative!!

Yes, it is nonsense, spouted and repeated by people who either don't understand the difference between what is a central bank rate versus a parallel rate ("street rate"), or want clickbait headlines.

You cannot buy bitcoin in Nigeria at the central bank rate -- only at the parallel / street rate.

As far as the actual rise in the BTC/NGN exchange rate? There will be some upwards pressure on the price where you might be able to get maybe up to a 10% premium for local P2P trading -- just like you can most anywhere else in the world too.