There is a thriving SA game development community:
http://www.gamedev.co.za/
Gaming is an international business. You don't see French developers just make "french" games, or likewise for most other countries. Sure, Japan and the US are special cases.
There have been successful local games, the two I can think of immediately were toxic bunny and there's a monster truck game on the Xbox 1, I don't know what its called.
The biggest issues are:
1. The game has to have global appeal to make it financially viable
2. You have to have someone with enough money to invest it the ASTRONOMICAL development costs of these things.
But if you're keen, go for it. It's one of the reasons I prefer the Xbox: XNA. It really reduces the entry level to get into game development. Regardless of platform, if you want to write games, do it. There are enough channels now with the likes of XBLA, PSN, whatever, that smaller projects can make money.
I'd advise you start as soon as possible - if you're a scholar or student, use your free time to get into the basics while your parents are putting a roof over your head and you don't need to do stupid things like work to pay the bills