Following your reasoning an airplane can't be hijacked because it's difficult to operate: in reality you only need a gun to operate anything, in right circumstances.
Also, it would be way way easier for us to track this sub versus what’s out there today. It’s way louder, I guarantee.
I don’t know about airplanes, but I’m a SWO qualified former naval officer that was onboard a sub hunting platform that we used to track narco boats and subs in different deployments, so I can tell you about ships and a little about subs since they share many similarities. I guarantee this type of sub isn’t used by narcos.