Look at the actual wording: Has the subject engaged in or discussed tradecraft to hide their online activities contextually different from previous activity?

Look at the actual wording: Has the subject engaged in or discussed tradecraft to hide their online activities contextually different from previous activity? The relevant part isn't the encryption, but the context. If you have two email accounts, one for general usage, unencrypted, and one encrypted that you rarely use, but suddenly see a spike in usage, that's a red flag. It isn't if you use encryption, but how you use it.