Make Uber Fragments Tradable on Exchange

Title.

I don't understand why everything stackable in stash (well, except incubators since those have ilvls) is tradable over Faustus, except uber boss (lvl 85) fragments. Heck, everything in the first 3 pages in the fragments premium tab can be put on the exchange, even things that don't stack outside fragments tab like Divine Vessel / Offerings / Legion Emblems, EXCEPT these uber fragments.

Did GGG just forgot about it or are there some deeper issues?