I'd like to offer a different analogy.
Encryption in communication is, to me, akin to the locks on the doors of your residence, on safes or other secure containers. It protects your privacy from prying eyes who want to snoop on what others are doing.
The activists are claiming that the government wishes to require that all locks be unlockable by one of a range of secret "master" keys, so that they can ensure you're not privately doing anything illegal. Not only that, but the government also wishes to institute a compliance regimen to ensure that all locks are indeed actually openable by these master keys.
Given the historic behavior of all governments, I don't trust them not to claim the most powerful interpretation of the laws and regulations that are instituted. Maybe not at first, but it will happen, because it has always happened this way.