How to reproduce

Create this entity file in a behavior pack

{
   "format_version": "1.17.20",
   "minecraft:entity": {
      "description": {
         "identifier": "test:invalid_events"
      },
      "events": {
         "add": {
            "add": {
               "component_groups": ["does_not_exist"]
            }
         },
         "trigger": {
            "trigger": "does_not_exist"
         }
      }
   }
}

Then load the world

Expected behavior

• A content log error informing you that the add event is invalid because there is no component group called does_not_exist on this entity
• Another one informing you that the trigger event is also invalid because there is no event called does_not_exist on this entity

Actual behavior
No warnings, the events load successfully but do nothing.

Notes
The vanilla behavior pack contains these kinds of schema errors.