Wow, 45-90Mbps for $3k-$6k/mo.
Companies and universities could, however, cough up for expensive alternatives, such as a diginet line which the ISP I worked for at the time offered. These guaranteed uptime (which was very appealing as ADSL outages were very common) but you paid a hell of a lot of money per 64kbps of uncapped bandwidth. You were looking at something like $400-$500 a month per 64k for the cheapest support package. And we weren't even the most expensive. There was a law firm that was paying something like $30k a month for their pimped out 2048kbps line.
Thank God things have improved dramatically there in the last decade (at least in terms of internet speeds).
The two primary causes for this situation was that the sole wireline telecomms company in SA and there were only 2 undersea data cables connecting SA (and I think Africa) to the rest of the world. Telkom was semi-private and state-owned so they had no incentive to improve things and also had to pay through the nose for access to the two undersea cables.
However, things started to improve when more undersea cables got laid down (lowering bandwidth prices and improving international bandwidth) and the government started lowering entry barriers so that Telkom stopped being such a monopoly.