The Client and Server are de-synced, the Server no longer sending the angle of attack to the Client (this.attackedAtYaw), and therefore the Client defaults to tilting only sideways to the left whenever you take damage
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Can I at least know if this Bug will be fixed in future versions of Minecraft?
It may be fixed eventually. But for now, Mojang has marked it as Won't Fix, and so it won't be fixed unless that resolution changes. It has been tagged for review, however, so they'll take a look at it once more to reconsider.
Duplicate of MC-26678.