African politicians still want 'their' airline. They still believe that it is a symbol of them (as indeed it is - but NOT in the way they think it is!).
You all know that SAA is not going to be sold off when they have just started selling tickets for some football matches to be held next year.
European governments wised up about national airlines in the 1980s and 90s. For African countries, it usually has to wait until things are VERY much worse than now, before they are allowed to go to the financial wall. Don't forget that you will soon have a new President who intimately understands the business of putting up a good show and he will want his pretty little airline to be there - even though he will never travel on it.
Just keep on paying the taxes ...