I believe that Cinema 4D will die out by next 5 years if Maxon doesn't present huge earth shattering updates that rock's the 3D scene. Sad to say this, but I'm so Hopeless about Maxon all-around. Moreover, Maxon is completely silent about what they hold for the future or if they are even working on any new additions in first place. Verifying this with the undeniable disappointing R25 which presented nothing new on the table.

Maxon is guilty for the state of Cinema 4D, due to the new Adobe's former manager who cares about showmanship instead of presenting new competing software features that could grab people's attention (like for example how Blender glorifies it's new tools in every release). I do not think Cinema 4D userbase will grow larger than now, because it costs money while having limited plugins and workflow compatibility compared to top leading competitors or free competitors. For me personally, i think Cinema 4D will hold a place for circa 200x artists who want a straightforward 3D DCC that they don't spend time fighting with it's UI.

Cinema4d cost