“A large number of MTN’s international carrier partners charge ITR’s significantly more than the rate of USD 0.25 as charged by MTN prior to the decision taken by Icasa,” said de Vries.
I've been closely involved in this field for years and the dynamics are very clear. There are millions of minutes coming into MTN from around the world. Foreign operators can contract with MTN directly or via other operators who have interconnects (as I did). The pricing is quite competitive and if one international carrier charges too much, another will do the job for less.
In one sense, incoming traffic is a monopoly as you have to ultimately go through MTN as a supplier to make calls to their subscribers. Much of the competition used to centre around least-cost-routing (using sim cards), which was the only workaround to the monopoly, but with the reduced MTR, this potential had decreased (until recently!).
MTN has a stake in BICS (Belgacom International Carrier Services) and wanted all international traffic to go through them. It also figured that if it inflated the price, it could boost the revenue via BICS. This is what one of our operators in Zimbabwe has done effectively via their international carrier (forcing international callers to pay >$0.30 when the local interconnect was $0.08).
The other alleged game (hard to prove) was to charge BICS lower interconnect and therefore capture a bigger share of the international market.
A number of governments have intervened to push the international rates up a little bit (Pakistan, Ghana, for example). I think this is excellent if it boosts forex for SA, but then the forex must actually accrue to South Africa, and there must be no dodgy deals to boost the rates (as is the case with Ghana, I suspect). Nor must the price be too excessive, as you penalise expats (ie in neighbouring countries) who have been forced to look for job opportunities elsewhere but still have family, friends and business contacts in SA).