OpenSCAD has it's origins in 3d printing (specifically the reprap project IIRC). Most 3d printing slicers[0] and firmware don't do curves[1].

[0] Some will import them now but convert them to triangles, cura can use a plugin to convert those triangles back to G2-G3 arcs or circles.

[1] at least by default, marlin has optional support for arcs that can be enabled at compile time.