Warzone 2.0 only:\n\n Xbox One: 70.0 GB. Xbox Series X/S: 62.0 GB. Battlenet: 23.6 GB. Steam: 22.6 GB.

This is correct, Warzone 2 is heavy on the CPU and would explain the GPU not being fully utilised. Increasing image quality settings (or display resolution) would increase GPU utilisation. Is the game running okay though? If so I would not worry too much that the GPU utilisation is not maxed out.