Piglin AI does not avoid falling off cliffs

I was on my Minecraft world with my friend and we were in the nether and I noticed a bug. Piglins kept falling off cliffs to attack mobs. I looked this up on the Minecraft wiki. Please comment it you are having this bug in a different version or on a different platform.

How to reproduce:

1. Build a nether portal and go through it. 
2. Find a cliff. 
3. /summon piglin
4. /gamemode 0

Expected results: The piglin runs round in circles on the cliff, but does not jump off. 

Observed results: It jumps off the cliffs to attack you.