Hashes are difficult to parse visually. You can have two hashes that look nearly identical.
Can you spot the difference between these two?
By hashing the hex, and using that to generate a colorful gradient, it‘s immediately obvious if two hexes are different.
You can‘t tell which character is different, but hashing makes it immediately obvious that something is off.
The sharp parts of the gradient make it easier to visually segment the text. This is especially helpful if you‘re doing a comparison of two hashes.