Why does extracting legendary power from Halycon's Ascent fail?

Kanai's Cube extracted powers are shared account wide (though there is still a separation between softcore/harcore and season/non season). This leads to some restriction with its usage like : Only Demon Hunters can slot the effect of an Xbow.

This also brings 2 majors restrictions in which items can be extracted and which can not :

• If the orange affix of a legendary varies depending on the class that loot the item (e.g. The Hellfire Amulet or The Halcyon's Ascent), then it can not be extracted.

• If the actual effect (i.e. the way it behaves in the game) of a legendary changes/destroys the item, then it can not be extracted.

  1. The Corrupted Ashbringer turns your weapon into Ashbringer for a short period of time which is not possible if you have a bow/wand/etc. slotted for weapon, thus making it unextractable.
  2. Ancestor's Grace is an amulet that drops only in hardcore mode that allows you to survive one death, in return the amulet is destroyed. This mechanic makes this legendary power unextractable.