"Hey! Your device creates and sends packages, could it just not create and send packages of this type? We'll even help with the quality control if you can't do it yourself! All we need is a backdoor!"
How is this not the same as messing with people's mail?
"Hey, you know this pen, paper and stamp thing? Can you just make the pen not write these kinds of letters, that terrorists usually writes? Ok, but can't we have a human (in lieu of AI) read through people's mail to make sure these types of letters aren't sent around with the intent to provoke violence? If you can't do it, we'll gladly send some agents to help you with quality control!"