Well, as you know a long time ago I did some patch editor and sysex app coding. But it's been years and years and things may have changed. If, for example, patch info is now stored as floating point numbers, extending the range on the synth user interface might not really impact the internal representation in a way that breaks the data format. But in the old days the internal representation and sysex was integer representation, and they typically used every single bit. So widening the range would mean either (1) adding more bits, breaking the internal data maps or (2) changing what the bits meant (i.e. 00000001 would mean a lower amount of amplitude than it did before) losing resolution and breaking people's patches.
Making a converter program isn't a big deal technically, but the user support problems are bad. They really don't want people posting to boards that "ASM screwed up the vibrato, and then my old patches didn't work any more, and then they had to release a fixer-upper conversion program, and it was a real hassle to download and useâ¦blah blah blah." And after the 50th email complaining "I installed the new Hydrasynth upgrade, and now the vibrato is broken on all my old patches" it gets really old.
So yeah, they could release a converter program and ask every one to dump, convert, and reload. But in the real world, and especially for a new company, that could be a dangerous thing in terms of user perception.
But all of the above is sysex as it was many years ago. They seem to be really bright engineers, and they could well have anticipated this kind of need and built-in something that is more adaptive than the old fashioned rigid methods allowed.
So unless someone on the inside has something to say, I'd chalk the above up to geezer speculation.