I can't speak for all avenues of the entertainment industry, but I can speak for the practical effects side of it. The company I work for has made 3d printing pretty much the backbone of its business, so almost 90% of what we do first goes through some form of DCC app before its becomes a tangible asset. What I have learned over the years is that each software has its place and are better suited for certain tasks. Moi3d has taken over the lion's share of my hard surface modeling due to the fact that I have to interact with the mechanical engineers that are building the animatronic substructures of what ever it is we are making. Being that Moi is a surface modeler its much easier on them to give them step files that they can directly work off of as opposed to an OBJ file that not many CAD programs can work with. That said I still use programs like Maya, Modo, Blender, Max to do certain jobs that just seem a little tricky to do in Moi in a timely manner. Like organic hard surface models that have a lot of compound surfaces that are just faster to do with SubD surfaces and don't require the cad like precision. For full Organics models like characters and creatures, Zbrush is used pretty much exclusively. So for me its more about what the job is and what is the best tool to get the job done in a timely manner. Pretty much every day I use a combination of Moi, Modo, and Zbrush to achieve my daily tasks. But again my duties are 3d print orientated.
For concept art, if your focusing on creature or character, Zbrush will probably get you 90% of what you need. If your looking into hard surface having some knowledge of a poly modeler will be useful, be it z modeler inside z brush or a traditional 3d animation packages like modo/maya/blender. Moi is also useful but probably more for a supplementary tool. Concepting need to be quick, and plenty of variations happen, so using Moi as a primary tool may not be the right choice unless your design very mech orientated designs. That said, Moi is still a hell of a lot faster than traditional cad programs like Fusion or Solidworks for getting an Idea out. Plus there are occasions where It can be definitely faster than traditional poly modeling when it comes to building clean hard surface shapes.

I guess where I am getting at is don't try to shoe horn everything into one program, leverage each program's strengths and mitigate their weakness. Knowing that you'll be able to maximize your productivity.

Cheers,
Greg