Drowned mobs has a piglin function that adds a drop to which is the gold ingot

I don't think that's a bug

Drowned have a 5% chance of dropping a gold ingot, increases with looting.

Similarily to how zombies have a slim chance of dropping iron ingots, drowned have a slim chance of dropping gold ingots.

I had no luck or looting swords and i got a gold ingot anyways