folder structure

anti_stone_iron/
├─ pack.mcmeta
└─ data/
   └─ minecraft/
      └─ loot_tables/
         └─ blocks/
            ├─ iron_ore.json
            └─ deepslate_iron_ore.json

- pack.mcmeta :
{
  "pack": {
    "pack_format": 18,
    "description": "No iron from stone pickaxes"
  }
}

- iron_ore.json (and deepslate_iron-ore.json) :

{
  "type": "minecraft:block",
  "pools": [
    {
      "rolls": 1,
      "entries": [
        {
          "type": "minecraft:item",
          "name": "minecraft:raw_iron"
        }
      ],
      "conditions": [
        {
          "condition": "minecraft:match_tool",
          "predicate": {
            "items": [
              "bettercopper:copper_pickaxe",
              "minecraft:iron_pickaxe",
              "minecraft:diamond_pickaxe",
              "minecraft:netherite_pickaxe"
            ]
          }
        }
      ],
      "functions": [
        {
          "function": "minecraft:set_count",
          "count": 1
        }
      ]
    }
  ]
}