I thought I saw a comment about using underscore to separate words in privilege names, such as EXCLUSIVE_BACKUP rather than running it all together. Was that idea discarded?
I'm not sure there was an actual discussion on the topic. Though, at one point I had proposed it as one of the forms of this attribute. Personally, I think it is easier to read with the underscore. But, ultimately, I defaulted to no underscore to remain consistent with the other attributes, such as CREATEDB and CREATEROLE.