Part of justice is enforcing a contract between two people who can and do consent. Would it not be an injustice if one person abused that system and hurt another?
At the rate cheap spinning laptop hard drives fail, you are literally an idiot if you aren't backing up important files. It's not IF they will fail, it's when.
There have been incidents of rogue upgrades to WinX despite a lack of consent; in such cases, your argument is moot.
Basically, people want to trust Microsoft to install updates it thinks are good and necessary, and then they get mad when they disagree with MS about what's good and necessary.
(Also, your attempt at doublethink fails because of GWX: how many other updates had a special pop-up notification "please give us consent to specifically do this"? Oh wait, zero, throughout the existence of WU.)