Golden Boots have the "minecraft:transformable_items" tag

The minecraft:transformable_items item tag is applied to diamond tier items that can be upgraded to netherite in a Smithing Table, however it is also applied to Golden Boots which cannot be upgraded. This tag should be removed from Golden Boots as they do not have a smithing transform recipe.

minecraft:transformable_items

• minecraft:diamond_axe

• minecraft:diamond_boots

• minecraft:diamond_chestplate

• minecraft:diamond_helmet

• minecraft:diamond_hoe

• minecraft:diamond_horse_armor

• minecraft:diamond_leggings

• minecraft:diamond_nautilus_armor

• minecraft:diamond_pickaxe

• minecraft:diamond_shovel

• minecraft:diamond_spear

• minecraft:diamond_sword

• minecraft:golden_boots