After a reboot, earlier, I saw this popup from WSA, which I decided was not applicable to me. I have no need to create an account, since I have no devices, e.g. Smartphone.
If you get the retail version later on and still only have 1 PC and no devices to manage, you still may wish to make an account if you desire to use the automatically enforced web-pushed settings, though you probably wouldn't have a need for that.
Unlikely, though...I don't see a need, as I have never needed to remove an infection, to date...touchwood! Plus, with a Closed Beta key...
This notification shows after you change local configuration for the first time just so that users know that they can manage it centrally You don't need to use it but it lets you manage configuration/detection/etc. from another PC if wanted.