In receiving the weekly quest reward on (4/30/24) from the “Last Hoorah” quest. I received a necklace “Suffused Choker” this item is still not socket-able, trying multiple times over multiple days through (5/3/24) to add tiered sockets to it. It says item can not be modified and remains greyed out.
Its also a drop from Cache of Awakened Embers. Even blue necks can be socketed.