An entity that is too far from anyblocks/ is on a block that cant support sculk veins will not drop experience points aswell as not spread sculk.
To Test:
Create an area of slabs using /fill ~ ~ ~ ~10 ~ ~10 minecraft:acacia_slab
Place a Sculk Catalyst and summon a pig
When killing the pig on the slabs, notice that no xp or sculk is created.
Thank you for your report!
After consideration, the issue is being closed as Working as Intended.
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