Giving a player an equippable item for a slot they do not possess causes that item to disappear completely when equipped by swapping or from dispensing. Inventory interactions behave normally and do not disappear the item stack.

I would expect the interaction to fail even if the entity is technically allowed by the allowed entities field.

This issue seems different from the Minecraft snapshot 25w03a changelog's 'Any mob can now have equipment added in the body slot as long as the component allows it', as equipping the item stack onto other entities works correctly: a sound is played and the equipment existed as verified by /data get entity @n[type=!player] equipment. In contrast, in this issue, a sound is not played, and the equipment does not appear to be stored on the player.

Steps to reproduce

1. Run {{/give @s minecraft:diamond_chestplate[minecraft:equippable=

]}}
2. Right-click while in survival mode
3. Observe that the item is nowhere to be found
4. Observe that /clear informs the user that there are no items