> the real danger of ECB is in interactive settings, where we as attackers get to induce plaintext patterns, and use chosen boundaries to isolate targeted ciphertext

Is it conceivable that actual Zoom use cases might allow attackers to do some of these things? I don't have an example in mind, but I'm thinking that the Zoom protocol supports many more actions than just audio and video transmission, so perhaps some of the other protocol features could be exploited for plaintext injection.

For example, Zoom supports text chats, and some kind of metadata information about participants and call setup. Perhaps those are all directly encrypted under the same key with the same block cipher mode?