The bug
Some mobs can auto-jump when on a honey block.
Affected mobs
Horse
Donkey
Mule
Skeleton horse
Zombie horse
Llama
Trader llama
Enderman
Turtle
Iron golem
Ravager
Pig (When the mob or player rides it)
Strider (When the mob or player rides it)
Drowned
Axolotl
Frog
Camel
Related issues
is duplicated by
relates to
Attachments
Comments

This autojumping behaviour could not be reproduced in Bedrock (PC).
Solo animals and mobs would not move up honey stairs. and neither could ridden animals move up.
have the same issue
Can confirm in 21w07a.
I've attached an example video.
Can confirm in 1.18.1.
Can confirm in 1.18.2.