Equipping a head item on your head with a different item_model does not change how it looks

Another easy one to reproduce. Here are two commands:

/give @s minecraft:carved_pumpkin[minecraft:item_model=ice]
/give @s minecraft:skeleton_skull[minecraft:item_model=ice]

Equipping the first item on your head: correctly appears as though a block of ice is on your head

Equipping the second item on your head: still appears as a skeleton skull, despite being explicitly defined as ice’s model in the item component

Expected result would be for the second item to also appear as an ice block when equipped on your head, as is the case with other items.

You can use this command to equip an actual ice block (with no custom components) on your head:

/item replace entity @s armor.head with minecraft:ice