player_hurt_entity advancement trigger doesn't work when hitting armor stands

Expected behavior
the trigger activating whenever the player hit's an entity.

Actual behavior
some entities, namely armor stands, bypass this rule

Steps to reproduce
1. summon armor stand
2. add this advancement into a datapack:

{
    "criteria": {
      "requirement": {
        "trigger": "minecraft:player_hurt_entity",
        "conditions": {
          "entity": {
          }
        }
      }
    },
    "rewards": {
      "function": "SOME FUNCTION"
    }
  }

3. notice the function doesn't activate for armor stands but does for other entities with hitboxes{}