Baby piglins never become adults. This might be intentional, as piglins (like zombies and zombie pigmen/zombified piglins) use the IsBaby tag instead of Age in order to determine whether a mob is a baby or not. <----- its not cuz only undead mobs never grow up
the only thing I see this to be intentionel is that its because time in the nether seems faster
- Spawn a baby piglin
- Wait for 20 minutes (two ingame days)
→ The piglin doesn't grow up.