Windows 10 Home, Java Version 8 Update 241
What I expected..
Hoglins spawn on a non-slab block ,and chasing after you.
What actually happened..
Hoglins spawn on the slab, being immobile
This naturally occurs when you load a bastion, i'm not sure about reproducing the bug, but it naturally occurs when loading a chunk near a bastion.
1. Enter Nether
2. Load a Bastion
3. Locate Hoglins spawning on slabs
I feel this ruins the challenge or purpose when encountering this structure, it would be better if they could spawn on a non-slab block.