There are differences in the loot table files for vaults between Bedrock Edition and Java Edition.

The exact loot table for vaults in Bedrock Edition can be found by going to https://github.com/Mojang/bedrock-samples/releases and navigating to "behavior_pack/loot_tables/chests/trial_chambers/", with the relevant loot table files being reward.json, reward_common.json, reward_rare.json, and reward_unique.json.

The exact loot table for vaults in Java Edition can be found by opening the game JAR file (using a third-party program to open archive files) and navigating to "data/minecraft/datapacks/update_1_21/data/minecraft/loot_tables/chests/trial_chambers/", with the relevant loot table files being reward.json, reward_common.json, reward_rare.json, and reward_unique.json.

These are the exact differences:

reward.json:

• In Bedrock Edition, the first pool has a 80% chance to pick reward_common and a 20% chance to pick reward_rare.
  • In Java Edition, the first pool has a 80% chance to pick reward_rare and a 20% chance to pick reward_common.

reward_common:

• In Bedrock Edition, the loot table gives 2-8 arrows of harming II. (aux value and data value: 25)
  • In Java Edition, the loot table instead gives 2-8 arrows of poison. (fixing the issue requires changing aux value and data value to: 26)
• In Bedrock Edition, the loot table gives 2-8 emeralds.
  • In Java Edition, the loot table instead gives 2-4 emeralds. (fixed in 1.21.0.23)

reward_rare:

• In Bedrock Edition, the loot table gives 1 block of emerald.
  • In Java Edition, the loot table instead gives 2-4 emeralds.
• In Bedrock Edition, the loot table gives an iron chestplate, enchanted from level 5-15, and has weight 3.
  • In Java Edition, the loot table instead gives an iron chestplate, enchanted from level 0-10, and has weight 2.
• In Bedrock Edition, the loot table gives an iron axe, enchanted from level 5-15, and has weight 3.
  • In Java Edition, the loot table instead gives an iron axe, enchanted from level 0-10, and has weight 2.
• In Bedrock Edition, the loot table gives a diamond axe with weight 2.
  • In Java Edition, the loot table instead gives a diamond axe with weight 1.
• In Bedrock Edition, the loot table gives a diamond chestplate with weight 2.
  • In Java Edition, the loot table instead gives a diamond chestplate with weight 1.
• In Bedrock Edition, the loot table gives 1 golden apple.
  • In Java Edition, the loot table instead gives 1-2 golden carrots. (fixed in 1.21.0.23)

reward_unique:

• In Bedrock Edition, the loot table gives 1 enchanted golden apple.
  • In Java Edition, the loot table instead gives 1 golden apple. (fixed in 1.21.0.23)

Attached screenshots show some of the differences in loot, such as different items being given.