Everyone knows odds of getting 3* ascension item are less and 4* even lesser. Getting odds for 3* item and finding out you are getting tall boots, chainmail shirt, scabbard, or battle manual is a slap in the face as most people start getting plenty of those after certain level. With Atlantis Rising event, you are likely to find many in loot.
Titans, Wars, Raid tourneys, chests should drop these at different rarity so they don’t hamper odds of non-farmable ascension items.
If they were converted to 2* rarity, I doubt anyone would even bat an eye.