It is 100% unnecessary but would be a nice quality of life and to remove some of the bloat from JEI, with all of the uncraftable ingots and all of the components and tools made from those ingots

for example putting Darmstadium into the search bar shows 93 uncraftable items that have 0 reasons to show up

While it's not possible to craft things like Darmstadtium, you can acquire some of these materials through dungeon loot so we do want players able to see what they can do with them in that circumstance. GTCE also tends to use Darmstadtium (or sometimes Aluminium) as the placeholder material for tools so it might be annoying if we remove it from JEI.

We already clean up a lot of JEI bloat. Cleaning up all the winding paths of GTCE materials that don't end up actually leading anywhere meaningful would be a considerable effort as there are hundreds of materials times tens of forms of each material.