Clearly very limited speakers that may sound 'nice and hifi', but not real.
Aluminium drivers were surpassed many years ago with far superior materials capable of higher frequencies without harmonic distortion, that may be palatable to many, but not by those seeking the original sound.
Machining material, cutting across grain bounderies always results in a poorer quality product prone to failure as it is not homogeneous. Forged materials are far superior, even if it comes from sheet material. Aircraft would never include machined components for critical stressed applications due to the high risk of failure.