Destroying a creaking heart doesn't drop any kind of XP

If you destroy a creaking heart without silk touch, the block will not drop any kind of experience, despite this being considered as a "mob kill" (i.e. Granting the player the "Monster Hunter" advancement).

How to reproduce

1. Find a naturally generated creaking heart, or place one.
2. Break the block in survival.

Expected result
The block would drop experience.

Observed result
The block doesn't drop any kind of XP, despite "killing" the creaking (if spawned).