I think you should mark Sodium as a dependency ("include" or similar) of Iris in Curseforge in order to give credit where due and potentially author rewards as well.

I've updated the 1.1.0 files to declare Sodium as an "Embedded Library", we'll need to remember to add Sodium as an "Embedded Library" in the CF metadata for future releases too.

We have JellySquid's (Sodium's Developer) Patreon on the description of the Iris Curseforge page, Iris in 1.16.5 came with Sodium in the same .jar hence there wouldn't be a dependancy marked to avoid confusion.

I am aware that it is in the description and that a dependency per se wouldn't be correct, however CF offers several options for marking it: