This datapack is updated for version 1.21, if you want the datapack to work for 1.20 or 1.19, just do the following:

1. Here in the ZIP of the datapack go to "data" > "minecraft"
2. Right in where the loot table folder is, add a leter "s" (changes from "loot table" to "loot tables")
3. After that your datapack is ready for 1.20/1.19