Or, perhaps the information being gathered from these calls wasn't too useful and embarrassing these agencies was judged more useful?
If they've gotten onto this phone call, one would imagine they can likely replicate this feat with regards to more detail-level meetings at one or more intelligence offices that were on the call.
And by exposing this call, they increase the level of doubt that any one agency IT team has that it was their network/phone system that was compromised. It's the ideal call to publicize.
