Paintings' pitch is wrong on the client after relog

Summary

As an entity, despite it's constant, the rotation of a Painting can be tweaked with /data. However, Painting’s rotation always looks as if it resets every time the save is restarted.

Steps to Reproduce

1. Place a Painting. Notice its rotation with F3 + B or in Spectator Mode.

2. Run: /data merge entity @n[type=minecraft:painting] {Rotation:[11f,45f]}. Confirm its Y rotation with /data get entity @n[type=minecraft:painting] Rotation.

3. Save the world and back to main menu. Restart the world.
   -> ❌ The pitch of the Painting looks as if it reset to 0, but running /data get entity @n[type=minecraft:painting] Rotation confirms it is still correct.