Monsters Hunted advancement has Zombie Pigmen in 1.16

Can't replicate. The vanilla datapack's advancement includes this:

"minecraft:piglin": {
      "trigger": "minecraft:player_killed_entity",
      "conditions": {
        "entity": [
          {
            "condition": "minecraft:entity_properties",
            "predicate": {
              "type": "minecraft:piglin"
            },
            "entity": "this"
          }
        ]
      }
    },

I can't see any reference to Zombie Pigmen.

My mistake, I thought it was a bug, but it turns out the last one needed was a Zoglin. Case Closed.