'Normal' cad software is parametric in an entirely different sense. You don't normally build up from entities just like you would in software, which you can then manipulate symbolically.
There are cad packages that can do this but unlike OpenSCAD the main interaction there is the 3D window, not the text editor.
Though AutoCAD of course had this with AutoLISP since 1986.
Interestingly, I'm not sure which has the steeper learning curve, OpenSCAD or AutoLISP. OpenSCAD is really great once it clicks but most people give up long before then.
Iirc autolisp applies to 2D drawings, so it's not a competitor for generating meshes
Mathematica however is Lispy enough and has a lot of helpful geometry primatives and can export STL
Interesting to read that. I don't remember any learning barrier for OpenSCAD, while FreeCAD and Rhino3D took many days before I had to put it down. I guess people differ...