Most people's mental map has basically all of Africa in the southern hemisphere, but geographically that is far from the case.

We have 195 countries in the world and only 33 of those are entirely on the southern hemisphere.

Here is one example of an illustrative map:

https://i.redd.it/w2tv9dda1xzy.png

Whoever came up with the term must think that the “south” starts at the tip of Italy

Yeah, basically. That puts almost all countries in Africa, and the Middle East, Mexico, India etc., in the "south".

Or not necessarily that the inventor of the phrase thinks like that themselves, but rather that they think most people think that way.

idk, the "West" seems pretty bad too