I don't understand what this would mean in practice. "End-to-end encryption" isn't really some fancy new technology. It's just the combination of communication

I don't understand what this would mean in practice. "End-to-end encryption" isn't really some fancy new technology. It's just the combination of communication plus encryption. If you and I share a password, I encrypt some data, email you that data, and you decrypt it, that's end-to-end encryption. So what would be banned? Would you not be allowed to email encrypted files to someone? That seems implausible. Would it be legal to email encrypted text files to your friends, but illegal to build software that automatically did both encryption plus email? That seems pretty weird, making it legal to do a thing but making it illegal to build software that made that thing easier.