> Whether or not the text is "divinely inspired" is a different point than whether it is divinely dictated
Thar actually depends rather strongly on whose understanding of divine inspiration you accept. While the term used is consistent, the range of beliefs as to what that term means is broad and extends the whole way to divine dictation.
> Of all the books of the Bible I can think of, none of them even claim to be divinely dictated - except for the ten commandments.
The decalogue isn't the only piece that claims to be directly quoting material that came directly from one or another person of the Trinity. (There's bits of the Creation story, the burning bush, and some other things scattered in the OT directly quoting the Father beyond the decalogue, and a whole lot of the NT directly quotes the Son.)
The decalogue is the only reference to a separate external document which was not merely divinely dictated by but written by the Hand of God, but it doesn't have any special claim of divine authorship beyond that of any of the other places God’s words in any form are quoted.