Development has slowed for Mud, but 3D Coat never gained enough ground and neither did Mari. I don’t foresee them killing Mud if anything they will migrate it into Maya and develop it as a whole.
Autodesk did kill Softimage but the line between Softimage and Maya is very thin, the only difference Softimage had up to this point is procedural workflow, that is suppose to come as BiFrost unwraps. What annoyed people the most was the fact that Autodesk didn’t release BiFrost with a node based workflow right away, as was done with ICE it’s going to be gradual over time, and I can sympathize.
As I said Autodesk could buy 3D Coat, or ZBrush or migrate it into Maya. I think Autodesk is slimming down operations, while The Foundry is where Autodesk was when it purchased Softimage, and what happened years later. ZBrush and to a point Mudbox has already made it’s mark, Mari is gaining some ground but I don’t think Autodesk cares what The Foundry is doing, first of all Mari is expensive compared to the rest and second, Autodesk is probably focusing on making better software, if you slim down you can offer fixes faster and improve software.
Mudbox workflow is different, but I see people like lots of icons, and in-your-face menus, as with Zbrush and to a degree 3D Coat. Besides Mud was a pipeline tool, is was designed to work in conjunction with Maya / Max. 3D Coat and Zbrush decided they rather be a modeling package, although this is debatable… The Foundry is doing the same thing with Modo as Autodesk is doing with Mud, whereas Modo and Mari work together, it’s still in its infancy but in time you’ll see.
Some of the sculpts done by Craig Barr, and Wayne Robson just to name a few in Mud have been remarkable, including hard surfacing, which I’ve done myself the results were pleasing. There are a few things Mud is missing, if those holes were filled, it wouldn’t matter. Everyone has there own take on what they like, you may like to paint, spec, diffuse, reflection at the same time, while someone else may want it separate, as Mud offers.
At this point, who knows what could happen, with any software !