[daniel1212]

and unless the MS magisterium makes an exception then you cannot legally transfer and activate your Windows to another PC

Doesn't apply if you are buying a used Dell (as in my example) that came with Windows 10.

That is a different story than taking the OEM OS on your Dell and legally transferring and activating it on another PC.

If you have a device that came pre-installed with Windows 10 (for example, Surface Laptop 3 and Dell XPS 13), then you are dealing with an "OEM" license. In this case, the product key isn't transferable, and you are not allowed to use it to activate another device. - https://www.windowscentral.com/how-transfer-windows-10-license-new-computer-or-hard-drive

[BiglyCommentary]

True, but if you buy a used system that you are going to use that has Windows 10 installed, it is a moot point.