Actually it makes perfect sense in terms of the timeline. At the time the 785 came out, there were almost no P25 systems out there; these were the days when trunking was undergoing a very slow transition to digital. Fast forward a couple of years, when more and more P25 systems came out, here comes the 796.
To be honest these are both ancient technology now; with P25 commonplace and Phase 2, NXDN and other modes on the rise, these old klunkers are getting left in the dust. Fortunately they can be tapped to use external decoders for these modes, but they'll never see any more support in terms of firmware fixes. They're both very much EOL (end-of-life)
Mike