A thicker desk mat won't save your wrists.

Not really. The thickness of a desk mat is pretty low on the list of things that matter for wrist comfort during long gaming sessions.

The real culprits are desk height, chair height, and arm support. If your elbows aren’t at 90 degrees and your forearms aren’t parallel to the floor, no mat thickness will fix it. A mat is mostly about protecting your desk and giving your mouse a consistent surface.

If you want wrist relief, get a separate gel or memory foam wrist rest (for keyboard and mouse). Desk mats are usually too thin—even the thick 5mm ones—to provide meaningful cushioning for your palms. They’re more about feel and aesthetics.

I’d focus on ergonomics and a proper wrist rest before worrying about mat thickness. A 3mm mat is fine. A 5mm mat is fine. The difference is negligible for comfort.

Your wrists will thank you for good posture long before they thank you for a thicker mat.