The bug
The dropping of scutes from growing turtles appears to be a hardcoded item drop, rather than referring to a loot table as with just about all other item drops from mobs.
How to fix
Introduce a loot table for turtles dropping scutes.
Linked issues
Comments


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Can confirm by code analyzation of Minecraft 1.21 inside
TurtleEntity.class
. I can also not find any loot table relating to this.