This is still in release 1.14.3. Testing various projectiles shows that it affects Snowballs, Eggs, Bottles 'o Enchanting, and Ender Pearls. It does not affect Eyes of Ender or Splash Potions. I've attached a video showing this (using the CustomModelData tag) in 1.14.3 with various items.
This appears to still be an issue if the item is the last item in a stack of projectiles, specifically when the hotbar slot for that projectile becomes empty. Since the hotbar never empties in creative mode, this can only be accomplished in survival/adventure mode. Projectiles from dispensers still render properly, even as the last projectile in a stack. I've attached a video of gameplay from 1.14.3 pre release 3 demonstrating this bug in action.
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Can confirm in 22w16a.
(I was hopeful that the fix to MC-81870, which also relates to entity rendering not updating after having data modified, would also resolve this).