Back in the days when Pluto was still a planet, and I had hair, circa 1988, there were two types of questions which were repeatedly asked of the satellite builders:
1. Why do you keep making me build a new modem to copy data every time you build a new satellite? Can't you just use a TNC? Why not fly a W0RLI packet BBS?
2. Why can't you just build a flying FM repeater, so I can use my regular equipment?
The techies who built satellites explained patiently both of these were Really Bad Ideas; both are extremely poor choices from a technical standpoint. They are single channel, and use one of the most inefficient modulation schemes known to hams. We have spent the past 25+ years proving the techies were right on both accounts. Consider the numerous detailed discussions concerning problems with both over the past few days. Those techies would be, and perhaps in some cases are, nodding knowingly at seeing the validity of those objections being born out.
But the users have also been proven right. Satellite APRS manages to work despite these limitations, and FM satellites are often in use AOS to LOS with normally good cooperation. (Everybody is a newbie sometime.) The ability to use rather simple equipment, easily understood, has won out over technically "sweeter" solutions. Users have tacitly decided that the limitations are a good tradeoff. The proof is the number of successful QSOs and Dxpeditions reported. However, the limitations are inherent in the chosen technology, and education, innovation, consensus, and courtesy can only do so much.
Keep in mind there are other voice options in the form of linear satellites now, and with only slightly greater complexity. You can chase DX, grids, and rag chew at the same time without taking away resources from other users.
To borrow a phrase from AMSAT-NA's Official Curmudgeon, Tom, K3IO, "But wait, there's more!" Digital voice and data systems are being developed by the current generation of techies which will make microwave systems, and the resulting bandwidth, available to the everyone using digital signal processing and eBay parts. As Phil Karn, KA9Q, puts it, any sufficiently advanced modulation scheme is indistinguishable from noise. But with that noise will come the ability to accommodate voice, TV, and data simultaneously. For some, the tradeoff of greater complexity for almost unbelievable capability will be worth it. For others, simplicity and familiarity will win out. In both cases, that is in the best traditions of amateur radio.
73s,
Alan WA4SCA Curmudgeon (jg)