No need to cherry-pick some random metric and try and justify a point that's not worth justifying.
I'm not justifying anything. I also think it's more polite to say "Ghana" rather than "Africa". I just don't agree with the arguments.
This goes beyond mere politeness; that you used this word is a bit suggestive. Refusing to acknowledge an identity is far more than just a lack of politeness.
Now, if you asked the same about Pakistan or Nigeria (#5 and #6 in terms of population, but far smaller and with far shorter sea borders), I'd bet that far fewer people would be able to pinpoint those with the same accuracy (whether in the English-speaking world or not).
You still need to know that it's the second-largest country in the world though
Asia is only ~50% larger than Africa.