That's really not the reasoning. The real reasoning is: "You consented to allow us to automatically install software updates on your computer. Windows 10 is a software update, se we installed it automatically."

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.

Well then. "We have changed your system so that your business-essential peripherals are no longer working (because vendor does not have drivers for Win10 just yet)" is good, yes? I sort of prefer to make such decisions in a non-automated and in-house way, so that the business case for upgrade can be considered on its merits. Instead there's unplanned downtime, because someone in a completely different company had to fill their quota of Win10 upgrades. Good and necessary for that person to get their KPI bonus, customers be damned.

(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.)

Windows 10 upgrade, no matter how Microsoft words it as an update, is actually a whole system replacement. So while most users trust Microsoft for keeping their system up-to-date, I don't think they approve its deletion and replacement by something else.

Then they misplaced their trust and should have picked a vendor they agree with more, because MS does think of it as an update. What "most users" think is irrelevant in court.