The Bug

Baby mobs tend to get pushed into one of the 4 corners of the block, when there is a high amount of mobs in that block. For cramming damage, they only consider mobs within the same corner for cramming damage, and not all mobs within the same block

How to reproduce

1. /gamerule maxEntityCramming 1
2. Go into one corner of the block
3. /summon minecraft:piglin ~ ~ ~ {IsBaby:true}
4. Quickly leave the corner to prevent the piglin being damaged by the player entity
5. Go into the opposite corner and run the same command again
6. Leave the block
   → The baby piglins do not receive entity cramming damage.