The Free Software Foundation (FSF) calls the update system used in Windows 10 a "back door" [1], I think because it installs updates automatically. This sounds like nonsense to me, because it implies that I installed a back door on my own machine by enabling automatic upgrades (on Trisquel).

It's meaningful that the Windows 10 install method has no (official) way to disable it, but I don't think making something optional could make it not a back door, if it was one before.

Even when automatic updates are disabled, I'm not going to be reading every update so the effect seems mostly the same, regardless of whether updates are automatic or not.

The FSF's definition of "back door" (at the bottom of the linked page) is "any feature of a program that enables someone who is not supposed to be in control of the computer where it is installed to send it commands" which leaves a lot of ambiguity with the words "supposed to be". I am not sure how to interpret this definition.

[1] https://www.gnu.org/proprietary/proprietary-back-doors.html#...