I assume this thread: I don't know why Ash.bulk_destory!/2 undefined bulk_destory - #3 by zachdaniel is you moving forward on the topic, but I will post a short answer here for others who end up here 
An individual destroy action is always modeled as just that, an individual destroy. We use Ash.bulk_destroy/4 to run a destroy action in bulk. If you want an action on the resource responsible for this, you would use a generic action.
