Gamerule doImmediateRespawn causes lag when killed

The bug

When enabling the Gamerule, doImmediateRespawn, it causes lag when the player has died after the screen freezes for 2 seconds.

How to Reproduce

1. Create a new world
2. Set the gamerule, doImmediateRespawn to true
3. Enable FPS + TPS by doing F3 + Alt, and use the /kill command