I just sent Nadee the following response:

I think the most up-to-date source of these numbers is the Wikipedia Diversity Observatory.

According to the "Extent of Geolocated Entities in Geolocated Articles" tab on its geography gap page, across all the geotagged articles in all Wikipedia language editions, 5.5% relate to Africa. If you look at unique places among those articles (disregarding multiple articles about the same place in different languages), 6.8% relate to Africa. On English Wikipedia specifically, 4% of geotagged articles relate to Africa (select "English (en)" in the dropdown box to see this).

Do note that the Wikipedia Diversity Observatory is a volunteer project mostly carried out by Marc Miquel, a professor at Pompeu Fabra University, so I would strongly encourage the reporter to credit him or the Observatory when using these numbers 😊

When WikiProject Africa says 1.47% of articles are within its scope, that is referring to the English Wikipedia specifically.

@marcmiquel Thanks for making such a great resource!