According to the documentation, the enabled key should support limited templates.
It appears templates do work for triggers. I say appears, because while the triggers I expect to be disabled indeed seem to never fire, it is seemingly impossible to tell from the traces view which triggers are actually enabled/disabled…?
For actions (and conditions) however, templates on the enabled key does nothing. Try putting in as simple a template as possible, like say enabled: "{{ false }}", and at least in my experience the action will still always execute. The only thing that will disable an action is a literal enabled: false.