Rhino UI is still pretty much a copy from AutoCAD back in the day. Even if you right-click a viewport-tab many of the menu items are the same. The “move or copy” dialog is almost 100% same.
I dont think a lot of effort went into rethinking the UI in the last 20 years, but IMO its still one of the best with its flexibility.
Rhino was originally an Autocad plugin The History of Rhino [McNeel Wiki]
This statement can only come from someone who hasnt really learned to use blender. Ive used autocad for years, then switched to rhino about 7 years ago and am proficient in it now, then picked up blender a couple years ago and I can assure you it’s workflow is superior to anything Ive ever used. Single key command engagements alone are a game changer (for example, num pad 7 for plan view, 3 for side view, 0 for camera, etc). No need to hit enter. Also, non destructive modifiers that allow you to do so many things (including arraying, thickness, etc) and go back to change them at any point. There’s also photo-realistic rendering and environments, which is a step above/beyond what we need, but depends on your client… And much much more but for us CAD people, just those two things are huge IMO).
I use blender and rhino in a professional environment daily, and I can tell you that what my clients are seeing out of blender makes them very happy.
Anyway, I love blender for modeling but I need rhino for the CAD construction drawings. I wish they got married and had a baby.