Not anymore. Ubuntu replaced the no OS option.

It's only Windows and None, they've replaced the pre-installed Ubuntu with an installation guide.
From FAQ:
You can choose the operating system that best fits your needs, Windows 11 and Linux are both supported. For Linux, Ubuntu and Fedora are officially supported with installation guides, and the Framework Community offers additional setup guides for many other distributions; other operating systems like OpenBSD may also work but are community-supported.