How can I make a piece of armor give the player no protection?
Solution 1:
Armor has an NBT value called operation, accessed like this:
{AttributeModifiers:[{Operation:0}]}
Operation is a value for how much armor protects the player. Operation:0 means the armor is purely cosmetic.
Try this:
/give @s minecraft:iron_boots{AttributeModifiers:[{Operation:0}]}