individual toolsets (2D Animation, Video Editing, VFX, Sculpting, Poly Modeling, Bone Rigging, Scripting – ALL with entire workflows associated with them) – has managed to be a wildly usable solution despite many of its individual subsystems working together.

Yup, I believe this boils down to good project management, someone has to steer those individual components so they work together better, in a cohesive manner, to make the result more than the sum its the parts. This is especially difficult in an opensource context where different contributors have different interests, and I think Blender, having managed that much, is an example to follow.

And I agree with everything you wrote, I don’t expect FreeCAD to get there in a reasonable timeframe unless it gets serious funding and expertise brought in.

Plasticity is a good project to follow, I don’t think they are comparable nor intended for the same audience, but there are product design aspects to learn from it, definitely :)