There was this research where faces were almost perfectly reconstructed from money's brain signals. How were they able to achieve such perfect recreation from monkey but not even close from human brain.
Because the macaque study didn't decode faces from fMRI. They first used fMRI to locate the face patches, then used tungsten microelectrodes for single-unit electrophysiology to record spikes from individual face-selective neurons in ML/MF and AM. [0]
Single-unit recordings capture individual spike patterns at a resolution fMRI, which averages across hundreds of thousands of neurons per voxel, simply cannot provide.
From my rather weak understanding on the subject, humans have a fast path for facial recognition over many other mammals. Some in some people this is otherwise broken or has been co-opted to fast recognize something else.