UnityWebRequest.downloadHandler.data not returning correct data as byte[]

I have data for a level stored as a base64 string

One of the ways works but it turns the raw byte[] into text format with www.downloadHandler.text, then uses System.Convert.FromBase64String to transform that back into a byte[]. I'm not sure why the raw byte[] from www.downloadHandler.data isn't working. Here is my code. LoadLevel takes byte[] as a parameter.

         private IEnumerator LoadLevelFromRawBytes () {
             using (UnityEngine.Networking.UnityWebRequest www = UnityEngine.Networking.UnityWebRequest.Get(url + fileName)) {
                 yield return www.Send();
 
                 if (www.isError) {
                     Debug.Log(www.error);
                 } else {
                     // This works. However, I don't want the string loaded into memory
                     LoadLevel(System.Convert.FromBase64String(www.downloadHandler.text));

                     // I feel like this should work but it's as if the byte[] isn't in the right format
                     LoadLevel(www.downloadHandler.data);
                 }
             }
         }