End crystals cannot be placed when any entity occupies the desired location of placement

The Bug:

End crystals cannot be placed when an entity occupies the desired placement location.

Steps to Reproduce:

1. Place down some bedrock and throw an item on top of it.
2. Obtain an end crystal and attempt to place in on the bedrock.

Observed Behavior:

End crystals cannot be placed.

Expected Behavior:

End crystals would be able to be placed.

Code Analysis:

Code analysis by Marcono1234 can be found in this comment.

Additional code analysis by [Mod] Avoma can be found in this comment.