The bug

The output of /attribute <entity> <attribute> modifier value get always outputs the unscaled value of the modifier, and makes no mention of the scale parameter, even if provided.
If run inside an /execute store, the stored value is properly scaled.

This is in contrast to /data get, where the command outputs the scale parameter (if supplied) and the scaled value.

Expected result

The command would mention the scale parameter and scaled modifier value, like /data get.

Steps to reproduce

1. Create a dummy modifier

   /attribute @s minecraft:generic.luck modifier add 01234567-89ab-cdef-0123-456789abcdef "Dummy modifier" 1 add
   

2. Create an example objective and make it visible

   /scoreboard objectives add example dummy "Example"
   /scoreboard objectives setdisplay sidebar example
   

3. Retrieve the modifier value, scale it by 5 and store it in the example objective

   /execute store result score @s example run attribute @s generic.luck modifier value get 01234567-89ab-cdef-0123-456789abcdef 5
   

   • Observe the unexpected output:

     Value of modifier 01234567-89ab-cdef-0123-456789abcdef on attribute Luck for entity [...] is 1.0
     

   • Meanwhile, the player's score has the correct value of 5.
4. Repeat the above, but via /data get, and scale by 10.

   /execute store result score @s example run data get entity @s Attributes[{Name:"minecraft:generic.luck"}].Modifiers[0].Amount 10
   

   • Observe the correct output:

     Attributes[{Name:"minecraft:generic.luck"}].Modifiers[0].Amount on [...] after scale factor of 10.00 is 10
     

   • Meanwhile, the player's score is updated to 10, as expected.