I have every volume of each drive connected to my Mac Mini set to a custom icon, using the same native method people describe above for folders/files. Am I missing something?
I don't understand the linked article either, as it says it doesn't work on ExFAT, but first thing I do on a new USB stick is Google Image Search a product photo, make it alpha channel, then turn it into an icon by pasting in Get Info for the mounted drive icon. Per the article this shouldn't work, but it does.
1: https://www.macworld.com/article/609302/want-to-change-a-mac...