useGLTF() has a boolean for the use or not use of meshopt. whether it's true or not has no influence on the final bundle size, leaving me to suspect, that the full decoder with its WASM package is forcefully included always: https://github.com/pmndrs/three-stdlib/blob/main/src/libs/MeshoptDecoder.ts

also the important update meshopt v1 just came out: https://github.com/zeux/meshoptimizer/releases and the three-stdlib is very behind on updates. That is tracked separatly here: pmndrs/three-stdlib#425