The latest Insider construction of Windows 10, 18309, expands the use of one thing that Microsoft has recently introduced: password-free Microsoft accounts. It is now possible to create a Microsoft account that uses a one-time code delivered over SMS as its primary authentication, rather than a regular password.
In the new Windows 1
While SMS-based authentication has its own security issues, Microsoft seems to feel that there is a better bet for most home users than a likely insecure password. Removing the Windows Login Password is part of the company's broader effort to switch to the use of a mix of one-time passwords, biometrics, and cryptographic keys.
The new building also includes a change in the installation process for Windows 10 Pro, Enterprise, and Education users: Cortana will no longer automatically talk to you and guide you through the installation process. This will make new installations of Windows 10 on multiple machines much less annoying. While Cortana's chats are useful for headless machines and can improve the availability of Windows users with vision problems, a whole room of computers talking through the Windows installation process is not a good time.
Comparing frustration is that while Microsoft is using Cortana to improve the availability of Windows setup, it has not done a very good job. As Paul Thurrott writes, Apple has done a much better job with macOS: the screen greeting starts automatically after a minute without interacting with the installer, and the narrative and voice controls are effective for the whole process. Cortana both encounters when she is not wanted and gives up for certain elements of the installation anyway.
Clean installations of Windows 10 Home will continue to have Cortana's story by default.