May I chip in here:
I've exchanged communication with Ken over the years and am also his customer. I think he is specifically calling Poser unsuited for professional animation productions intended for commercial distribution. There are many artists who render professional quality still images using Poser, and it would be an outright insult to call their work non-professional. Also, many merchants create commercial products which must pass a certain quality bar, oftentimes equivalent to professional grade work. It would be an insult to imply that theirs is anything but professional quality output. Hence, to summarise, Ken Watanabe was only making the point for animation productions intended for commercial licensing and distribution.
In a sense, people sometimes commission me to make Poser renders, and, by definition, anything people pay you to make can be considered "professional" work. I know of online book stores that hire Poser artists to make covers of commercially sold books, so that could fit the bill as well. I think this might have been where Poser renders have been used commercially the most - book covers. Digital Art has promoted some of that in their webinars, and I have seen book covers where I kind of recognize a Poser render. There were also digital comics sold commercially with Poser renders, though some of these have been heavily painted over for the final art. Content creators sell their products at online stores like HW, Rendo and DAZ, so these people could be called "professionals". Even Rooster Teeth has advertised about Poser in the closing credits of every episode of RWBY's first commercial season.
Having that said, people could say they have used Poser commercially for years, to include myself, but I guess my point was that Poser does not come to mind when commercial companies think about creating a professional animated series. This is where SMS has advertised Poser being "the ultimate professional animation tool", because Rooster Teeth was using it on RWBY's first season. But the fact remains that Rooster Teeth has switched to Maya for the second season on because of Poser's technical limitations in features and performance. It was just not up to the task, where anyone who has tried to animate in Poser will realize.
That is not to say that Poser cannot animate characters - I have posted DOZENS of Poser animations at DA. I just think it would require a more "serious" tool set to allow for professional grade results. If I had to make suggestions, I would start with better IK, and adding foot and hand ground contact. For example, Reallusion iClone uses Autodesk Human IK and supports feet and hands ground contact in real time. Those things alone could make iClone more "professional" than Poser for commercial animation. Even Disney has created a real-time animation division that does all the work using the Unity3D game engine to create episodic series. Poser is much older than Unity3D, so why didn't Disney pick it instead? Because it's not up to the task.
Most of the Poser code is now 20 years old, and it's showing its age. iClone and Unity3D are constantly being upgraded and improved, while Poser is stuck in the past. Even the Cycles rendering engine in Poser is stuck in the past, while Cycles in Blender3D has evolved and improved in many areas since then. It's now up to Renderosity to bring Poser out of the shadows and to the present day. Maybe then Poser could be considered for professional work, but until then, like DS, it remains a low budget hobbyist tool.