Question [HELP] Compare the fbx files of Maya and Blender when imported in Unity.

I do an animation file in Maya, I've been exporting like this for 4 years.
My file has a model about 5000 tris, about 95 joints, and I will export in 2 parts
+ 1 fbx file contains only model and bone, it will weigh around 600kb.
+ 1 fbx file containing only animation bones, with about 30 frames will weigh about 1.3mb.

But the problem is that if I bring the file containing only the animation bones to Blender for export, the file only weighs about 600kb and still WORKS GOOD IN UNITY. I'm trying to figure it out, but I can't find any information that explains this, I've tried turning off many of the functions in the export in Maya, but it's only a little lighter, not as light as Blender. .