The fall damage calculation for horses, donkeys, mules, zombie horses, skeleton horses, camels, llamas, trader llamas, and foxes does not consider the minecraft:generic.safe_fall_distance and attribute. Notable, setting the minecraft:generic.safe_fall_distance for these mobs to 0 doesn't result in them taking fall damage when falling only one block, unlike other entities. However, it does cause them to produce fall particles upon landing on a block as anticipated.

Steps to reproduce

1. Summon a horses, donkeys, mules, zombie horses, skeleton horses, goats, camels, llamas, trader llamas, or frogs

2. /attribute @e[type=minecraft:horse,limit=1,sort=nearest] minecraft:generic.safe_fall_distance base set 0

3. /execute as @e[type=minecraft:horse,limit=1,sort=nearest] at @s run tp ~ ~1 ~

Observed: The mob didn't suffer fall damage but emitted falling particles after falling one block. Expected: The mob should also incur 1 health point of fall damage.