The mob with delay attack (Ravager) can't hit iron golem

In this video we can see after knockblack resistance system change, ravager no longer can touch or even bite the iron golem at once. Also I tested to change other hostile mobs attack pattern by behavior pack ("minecraft:behavior.melee_attack" to "minecraft:behavior.delayed_attack" ). The mobs have delay attack sometime would "delay" while tracking target.

Ravager issue

1. Create a Iron golem

2. Spawn a ravager.

3. Ravager in 1.16 can't attack the iron golem anymore.

"minecraft:behavior.delayed_attack" issue

1. Custom a hostile mob (for example: vindicator or zombies) with this json code. 

2. Spawn a target mobs nearby this hostile mob

3. The hostile mob sometimes delay while tracking and can't touch the target mobs. (Similar the bug MC-196449)