Given support for a non-3D print program like GibbsCam (which I didn't know 3DS owned, and barely knew existed), for which there is sufficient competition, one would suppose GMD would be getting similar attention. Gibbscam is an outlier, and to some degree GMD is also, although GMD does actually have direct applicability to 3D printing, where the CAM program does not.
If there was an intent to drop all "non-core" products, the CAM program would seem to be the first to go. VERY MUCH non-core, has active and successful competition.... it would seem to be a no-brainer to declare it to be of limited payback potential and spin it or drop it. If, as it seems has been asserted, the CAM program has active support, then that would seem to be a positive indicator.
Similarly, dropping the various sub-variants of GMD would seem to have been a positive. They basically were threatening to bleed GMD's own core development of resources. Picking a low end (Cubify) and a main (GMD) version, where one is a defined subset of the other, can allow more directed development at lower cost, with fewer compatibility issues.
As for lack of info, it is definitely not customary to release info about a new or enhanced/updated product until the release date is near. If you give out info, especially info about what you intend to do, however nice your users may feel about that, you also alert the competition to what you are doing. That is, in general, not a winning strategy for a company which does not have a virtual stranglehold on the market. Microsoft can get away with it to some extent, but lesser players in the OS or the office software areas cannot.
I doubt that even Solidworks would lay out their plan for all to see. Some of it, maybe, definitely not details. And even then, not until fairly close to release.
So, there really is not a reason for so many to be so negative about GMD. It's better to wait before dismissing it.
The claim by 3DS that they are indeed working on it suggests to me that they may be integrating an updated engine, or doing other similarly basic changes. If so, that may be very good news, since there seem to be some deficiencies in the program now. We have all pointed them out, and been irritated severely by them.
In any case, no matter what you think about timely and frequent updates, the last few updates have been largely incremental. A feature here, a compatibility there, nothing to address things that have been known for several iterations. Even the Keyshot integration is essentially an upgrade, since there was a .Bip file export to begin with. A period of apparently lesser activity often tends to precede a major revision (or, of course, cancellation, for those who insist on "taking the low road").