Show HN: Parametric sound absorbing structures that you can 3D print (github.com)

While fascinating, this approach to manufacture appears to attempt to use a low efficiency method. Why not start with a sheet of plastic, and drill or pierce with holes?

Vacuum based plastic tooling has been around for a long time - would it not be more appropriate to use the 3D printer to generate the shape of the mould?

Not so low-cost: 300$