I disagree with your analysis — the way most people receive encryption, including criminals and terrorists, is through a provider. Regulating their behavior does change the general trend in security. Further, forcing them to implement their own encryption increases the likelihood they make a mistake while also refocusing the NSA et al to those algorithms instead.
What we’ve seen is governments subverting encryption and systems repeatedly, in ways they wouldn’t if they had other methods.
I’m not trying to accomplish some absolute ideological position, I’m trying to shift the state of affairs to realign incentives for several players. If some people write their own encryption, or the technologists use GPG everywhere, whatever.
> allow them to have a society-wide dragnet
I don’t think you even read my proposal: the mechanism I proposed makes that impossible, which is in contrast to the current state of affairs, where they subvert the security of the entire system instead of targeted people. Allowing for targeted cracking at a certain level of expense and requiring physical possession of the device in no way enables mass dragnets, and in fact, removes their legal cover by providing alternative means.
I’m not saying people can’t invent their own security — just that factory made safes need to not be “unbreakable”, because it just incentivized bad behavior when they discover a flaw and/or subverting the integrity of the factory.