Materials should not be associated with MeshPrimitive because MeshPrimitive can be reused

I think saving the material index in MeshPrimitive may not be a good design We would like to use the functionality of glTF. We need to frequently handle oversized scenes and reuse meshes as much as possible, but MeshPrimitive is associated with materials, which can lead to the generation of more mesh objects, even if their vertices and indexes are consistent.
Why not add an array to save the index of the material in node? The array should not use more memory than MeshPrimitive.

Start by reviewing how glTF represents MeshPrimitive reuse, node material associations, and material indices. Compare the current MeshPrimitive model with the proposed node-level array, then determine the affected specification or implementation files and define compatibility and memory requirements before making a change.

Written by the indexing model from the issue text.