To start, Minecraft has two different reaches when you are in survival mode: an attack reach (3 blocks) and a building reach (4.5 blocks). You can see this here https://minecraft.fandom.com/wiki/Player#Reach. However, the code in PlayerConnection.patch (near line 1164) for detecting a PlayerInteractEvent with Action.LEFT_CLICK_AIR checks to see if either an entity or a block is within 4.5 blocks. This means that if a Survival player left clicks at an entity who is outside of its attack reach but still within 4.5 blocks, neither a PlayerInteractEvent nor a EntityDamageByEntityEvent will be called. This seems like unintended behavior because the player actually is left clicking the air.

I've also included a plugin that messages the player when the PlayerInteractEvent is triggered and when the EntityDamageByEntityEvent is triggered (by the player). To recreate this issue:

1. load the provided plugin
2. set your gamemode to survival
3. find an entity
4. left click at the entity while you are further than 3 blocks away from it, but closer than 4.5 blocks from it

You will see that the entity is not damaged and that the interact event is not called.