Bitcoin trading mainstream in China, however Nigeria is not among the top 10 countries trading Bitcoin , could it be that Nigeria government have not legalize Bitcoin?why is China among the top 10, but Nigeria isn't?
There's a crackdown that's happening in China and you'll see that there will be a drop in volume there. And in Nigeria, AFAIK, there's also a problem that makes them stop most crypto transactions. It isn't important if they're from the top 10 or not that has the most volume.
Both countries are known to have huge volumes but also have complicated status about their insight towards bitcoin.