While investigating why Gibbed Tools wasn't compressing normal maps correctly, I discovered something quite interesting:
Every single normal map in the game is compressed incorrectly resulting in both the red and green channels containing the exact same data. This means all the normal maps are wrong. This seems to have happened somewhere between the last Early Access update and the first full release of Reincarnation and has not been fixed since, which I figured out by comparing normal maps from the two versions. For example, this is what the TunnelGrille_n.tdx texture has looked like since full release and still does in Max Damage:
As anyone with any experience of normal mapping can see, that is completely wrong. This is what it looks like in the Early Access of Reincarnation, which is correct:
To further illustrate the problem, here is a screenshot of Caddy Fat Cat in Max Damage, note the air vents look very bad as it goes towards the end as the normals are pointing in the wrong direction:
Just replacing the normal map with the one from the Early Access build and, et voila, it looks so much better because the normals are pointing in the correct direction:
This problem is in every single normal map I have looked at in Max Damage and really diminishes the visual quality of the game compared to how it should look if the normal maps were correct.