The bug

Unlike what the trigger name suggest, you can't detect what the original block was for the item_used_on_block trigger. The location condition is evaluated after the block change was made. This makes it impossible to detect some actions.

How to reproduce

1. Create the following advancement.

   {
     "criteria": {
       "place": {
         "trigger": "minecraft:item_used_on_block",
         "conditions": {
           "location": {
             "block": {
               "block": "minecraft:dirt"
             }
           }
         }
       }
     },
     "rewards": {
       "function": "test:tilled_dirt"
     }
   }

2. Create the following function

   advancement revoke @s only test:tilled_dirt
   say used item on dirt

3. Use a hoe on dirt
   Notice that the advancement is not granted
4. This advancement will be granted correctly when placing block on dirt, because the dirt itself does not change
5. This can also be verified by checking the state of button presses.

Fix

An easy way to fix this is by adding a "block" predicate to this trigger. Triggers like bee_nest_destroyed can already check the original block.