A lot of memory with GLTF

Thank @donmccurdy,

I also found out another thread about how to reduce the file size of glTF model which use gltf-pipeline as mugen87 suggested in this thread.
However, I’m still stuck in reducing file size of my model.

My original file is 43.4MB, but when I do:
gltf-pipeline -i MyModel.glb -o modelDraco.gltf -d
and the new file is made with 51.3MB in size.

The other option to do is:
gltf-pipeline -i MyModel.glb -o model.gltf
But the new file is 57.9MB in size.

Am I doing anything wrong?
Thanks,