Large and continuous lag spikes sometimes occur when loading/reloading into a world in 21w37a

The Bug:

Large and continuous lag spikes sometimes occur when loading/reloading into a world in 21w37a.

This issue did not occur in 1.17.1. This may be quite difficult to reproduce as this does not happen all of the time.

Steps to Reproduce:

• Create a new world in 21w37a.
• Exit the world.
• Join the world again.
• →  Notice how large and continuous lag spikes sometimes occur when loading/reloading into a world in 21w37a.

Expected Behavior:

The expected behavior would be that no large and continuous lag spikes would sometimes occur when loading/reloading into a world in 21w37a.