I'd write this as:

```clj
(defn content-deleted? 
  [deleted-items org-name env-name content-type & [repo-name]]
  (let [all-items (if-not repo-name 
                    (map :name (get-content org-name env-name (content-map content-type)))
                    (try
                      (map :name (get-content org-name env-name repo-name (content-map content-type)))
                      (catch IllegalArgumentException e (list))))]
    (not (some (set all-items) deleted-items))))
```