Texture looks flat

Hi texture wizards here.

I am having trouble with one texture that doesn't want to play along.

First let's look in Blender

The left wire is part of the cable gutter; the right cable is a separate one that is added to the model when selected. Below you see both textures for the complete gutter (left) and only the cable (right, generic blue texture for multiple use cases). Both have the same color of blue on it,

Then come the mga textures. Once again, the blue parts have the same values.

Both mtl files are set up the same

Yet somehow, in-game, the right cable looks flatter than a pancake.

Am I missing something complete different here?

Hope anyone can help me out on this one

That's why I'm baffled in this situation. All normals are flipped the right way (as seen by the red inside of the tube)

Tried clipping in in-game. Shading difference is still visible

Dove a little deeper and noticed there is a discrepancy between the side the normals show between Blender and the ModelEditor

Where Blender renders the normals al the way around the model, somehow after exporting, the ModelEditor decides they should all point in the same direction. Does someone know what makes this behavior happen, and even more necessary, how to fix this?

Who would have thought, ChatGPT to the rescue

It gave me as a possible solution to check Clear Custom Split Normals Data in Object Properties. Never had to use this option and don't know why but it fixed the flat looking texture.

And in-game

Just sharing if someone else might encounter this in the future.

Greetings