Its probably the anistropy like @Harold suggested.
See my working example. I don’t load a pre built glb but create a SphereGeometry and texture it using a 5400x2700 jpg in the code.
You can view the source from the <> button in working demo.
It uses Three r130
Three.js TypeScript Tutorials by Sean Bradley : https://sbcode.net/threejs
Change the anistropy slider
With anistropy 16
With anistropy 1
You may be able to traverse your glb, find the texture and set it.
I.e.,
texture.anisotropy = renderer.capabilities.getMaxAnisotropy()