AFrican teams really aren't good enough, you only need to look at who African nations play, the worst thing is most of them have basically no history whatsoever in playing teams outside of the African nations, most of the teams have stuffed in a few friendlies since the ACN in Jan but before then some haven't played Euro/American/Asian teams in years.
In the friendlies there was barely a single good result amongst any of them, someone drew with Italy, who haven't won in ages, thats about it, losing most games to the worse Euro/Asian teams isn't a positive review of their abilities.
Theres no reason a home nation has to be good or get through to latter rounds, its good its somewhere very different, and the Korea/Japan world cup was great aswell.
Hopefully though this ends up being good experience for the African teams and in the next several years they'll become a lot stronger and play a LOT more friendlies with teams from other continents, which will again improve them as teams.