My guess is:
Examples aren’t only for learning, they also a “test bench” for new/future releases to check if supported features didn’t break along the way. This is typically how it was done since the dawn of three.
In this specific case the main feature use canvas FlakesTexture.js and clearcoatNormalMap (clearcoat probably the only part requiring changes).There is very little chances to get a performance gap. The strong side of webGPU is more obvious when shaders are involved to manipulate meshes and textures, enabling previously unthinkable move (like massive instancing and procedural generation). So yes you 100% right