I'm not sure if this is intended or not, but zombified piglins keep their arms at their sides when attacking a target, rather than raising their arms like other undead mobs do. A good example of what is expected is the wither skeleton; it keeps its arms to its sides when idle, but when attacking, it raises them like a zombie does. Even regular skeletons raise their arms to attack if not equipped with bows.
Since the zombified piglins will be replacing the zombie pigmen, it would be nice for them to retain the attack animation of their predecessors.