This is highly unlikely in my opinion. At least a few of such civilizations would absolutely retain the ability to and actively track EM and more primitive methods of communication for no other reason than intellectual curiosity. Just consider how much time humans spend on such endeavors.
Well, that and [shared sensory experiences] just [feel/digest/reflect] better when they’re transmitted via EM. [untranslatable concept] gives a more accurate, high-fidelity reproduction, sure, but I have always found the EM distortion pleasing to the [untranslatable sensory apparatus].
