Can someone answer why is this ok on iOS and macOS but not Windows?
They all provide backup via their own paid clouds and ask for an opt-in.
They all provide backup via their own paid clouds and ask for an opt-in.
Microsoft is using all the levers at their disposal to force users to use online Microsoft accounts to log onto their local computer and even turn on formerly optional features like One Drive.
My assumption is that Microsoft is using their access to user data to build up everyone's advertising profile, and forcing you to be logged on through a Microsoft account makes sure that the data they collect is linked to a specific person.
Windows Recall is another example of a "feature" they wanted to force on users that can be used to fill out everyone's advertising profile.
Also it should not be locked to a single online storage provider but use some sort of standardized protocol (or at least some pluggable mechanism) to allow any online storage provider - including using self-hosted options - to work with it.
This is how you make something that works for your users instead of taking advantage of them.
(I've had it turned on for so long that I honestly don't know what they do.)