I know, it's just that in this particular blog post, the designs mostly seem to be extruded 2D sketches which solvespace is particularly good at with its sketch

I know, it's just that in this particular blog post, the designs mostly seem to be extruded 2D sketches which solvespace is particularly good at with its sketch interface. Solvespace can also do a lot of useful 3D stuff, but it's also missing a lot so I can't in good faith recommend it for any arbitrary CAD work.