Prior to 1.14 or versions above 1.14, the limbs of most entities no longer move during death animation. Instead their legs are stationary and will not move. This includes, the flappy ears of the piglin and hoglin, etc.
MC-168187
Entity limbs no longer move during death animation
Open
13
(Unassigned)
Confirmed
Gameplay
Low
Rendering
1.14.4, 19w45b, 1.15, 1.15.1, 1.15.1 Pre-release 1, ..., 1.18 Pre-release 2, 1.18 Pre-release 5, 1.21.1, 24w39a, 1.21.4
Retrieved
Can confirm for 1.16.2 Pre release.