How to reproduce

Create this entity file in a behavior pack

{
   "format_version": "1.17.20",
   "minecraft:entity": {
      "description": {
         "identifier": "test:crash"
      },
      "components": "crash",
      "component_groups": {
         "crash": "yes"
      }
   }
}

Then load the world

Expected behavior

• Content log error informing you that the "components" field should be an object instead of a string
• Content log error informing you that the "crash" component group should be an object instead of a string

Actual behavior
Game crashes