Haven't there been oval mouthpieces before?

The short answer is: yes, there have been oval mouthpieces before. However, the rim design of those mouthpieces followed the shape of the lips, increasing contact with the mouthpiece. The long axis of the oval was oriented side to side and curved around the embouchure sideways.

This is exactly the opposite of the Wedge. The Wedge oval goes up and down while the rim curves away from the corners of the embouchure, not around them. The idea is to decrease pressure and surface contact at the corners of the mouthpiece. The result is better circulation to the lips within the mouthpiece rim, greater comfort, less swelling, and a greater ability to adjust the central embouchure aperture.

Have there been oval mouthpieces before? Yes. But there has never been one like the Wedge, which offers a completely new approach to the oval mouthpiece.