Wither shoot at the hard difficulty level doesn't give The target mobs wither effect like in the easy difficulty level

When the wither shoots me on easy difficulty, it doesn't give me the wither effect, and on normal difficulty, it does, but on hard difficulty, it doesn't.

Steps to Reproduce:

[Step 1] Prepare something that won't kill you from the wither, such as running this command

/effect @s regeneration infinite 225

  [Step 2] Summon the wither on easy difficulty

  [Step 3] make sure it attacks you

  [Step 4] change the difficulty to normal

[Step 5] change the difficulty to hard

[Step 6] compare the results

Observed Results:

Shooting the wither on hard difficulty doesn't give me the wither effect as on easy difficulty

Expected Results:

Shooting the wither on hard difficulty gives me the wither effect

Notes:

• Earlier versions of Minecraft did not experience this