> unless the OS vendor doesn't trust even the owner of the hardware/licensee of the software and has taken effective countermeasures against diving deep into the software (Linux, of courage, has not).

This is not entirely true.

SELinux does allow you to lock down certain actions while leaving root access available.

And of course you can configure selinux to prevent root user from disabling selinux.

So you might have root access and the game would not be over.