Players can reach mobs from one block further in creative mode than vanilla

Minecraft Version: 1.20.1

Forge Version: 47.4.13

Logs: {Link(s) to GitHub Gist with full latest.log and/or crash report}

Steps to Reproduce:

1. Spawn mob using a command to specify location and no AI
2. Move 6 blocks away from mob

Description of issue: You can hit the mob when you cannot in vanilla

Here's proof I used the same world: Forge 47.4.13:

Vanilla 1.20.1: