I am pretty sure, a nation state wanting to hack an individual's system has way more effective tools at their disposal.
What the hell is more effective than getting root with a trivial MITM?
Not only is it effective, it's stealthy, in that it doesn't out you. It's obviously possible to both find and exploit it without a huge investment, which means nobody knows you're a nation state when you use it. You don't have to risk burning any really arcane zero-days or any hard to replace back doors.
Nation states are absolutely going to use things like that. And so is everybody else.
Don't understand why most people mean auto updating software would in any way create more security. It just creates more attack vectors for every software that has a auto updater.
An auto-update mechanism only becomes an RCE if it allows unauthorized third parties to execute code on your machine by failing to verify that the code comes from a legitimate source.
> you just need the key
Secrecy of cryptographic keys is the basis of all cryptography we use. There's no "just", you need the key and you don't have it.