Further, why a political solution won't work is right there: this is not an issue most people face or will care about. Even if you manage to stop customs agent

Further, why a political solution won't work is right there: this is not an issue most people face or will care about. Even if you manage to stop customs agents from demanding access, some other branch of government will do it, even if it's outright illegal for them to do so. Technical solutions are the only ones that will make a dent.