So I'm guessing this also means they can't climb ladders either?
Since we have an entity (Alexander) that can float, and maybe even some others, I can't recall though, wouldn't it be possible to have an enemy that could "float" upward upon collision with a ladder/wall and then have the animations of their arms and legs simulate the act of climbing?
Actually, can enemies do other things like, say, leap across platforms, or even walk up stairs? I don't think I've ever seen an Amnesia enemy (if you don't count the lethal red mists of lethality) in the main game or in a custom story, that ever walked up or down any stairs, so I'm curious. If not, then that would be a pretty bad downgrade from Penumbra's dogs which chased me up stairs and killed me more than a couple times.