whenever i summon a mob with an elytra that is fallflying it doesnt use the extra bits of its ai (such as zombies chasing villagers) it will still turn mid flight but not anything else as far as ive seen and once it lands it behaves normally
steps to reproduce:
step 1
spawn villagers nearby
step 2
use this command to summon a zombie thats moving upward and flyfalling with elytra
/summon zombie ~ ~ ~ {Motion:[0.0,1.0,0.0],IsVillager:0,IsBaby:0,ArmorItems:[{},{},

{id:elytra,Count:1b}

,{}],ArmorDropChances:[0.085F,0.085F,0.0F,0.085F],Attributes:[

{Name:zombie.spawnReinforcements,Base:0.0F}

],FallFlying:1b,PersistenceRequired:1,Team:"Red",DeathLootTable:"null "}
step 3
watch zombie completly ignore villagers until he lands