Crane Currency uses Blender in the design of the micro-optical animations of their Motion and Surface security threads that are integrated into banknotes around the world. Check out a US $100 bill for an example of the results. In my previous role there, leveraging Blender's flexibility for integrating functionality via the Python API into various parts of the UI was great.

I wish there was an open source CAD/CAE application that would copy a few of Blender's workflow ideas (integrated REPL, 3d view, node editor, text editor, high level language API).

All Blender is missing is 64-bit vertex storage and 2D data plotting and it would also be the perfect dashboard bridge between the physical engineering/design and data science worlds in addition to its primary audience of 3D content creation, but it's hackable enough to work around those few limitations.

The recent Netflix animated movie 'Next Gen' was made in Blender. The production company is also contributing enhancements they made to Blender back to the main project.

It's not just for amateurs.

Much of the 3D work for Man in the High Castle is done in Blender, as Barnstorm VFX is a Blender shop. While not used widely, there are pros using it in big productions.