Not really, because the proposals aren't to go to no encryption but to go to government-backdoored encryption. To an observer you've still just a random stream of bits until someone tries to decrypt it with the backdoor key. Pretty easy to hide in unless we're monitoring every message.

And terrorists would be smart - they'd employ non-backdoored encryption, hide that in "legit" communications, and encrypt that with the proper back-doored government encryption. They'd appear to be a totally normal snapchat user, or whatever.

If we actually meant to give up all encryption, card-kiddies would destroy civilization in three weeks.