It's not explicitly labeled as CC on the license page, but maybe it's still considered CC due to the wording: https://openby.design/license.html

An asset is typically the final rendering of something, not the source that was used to develop that asset (image of design on Dribbble vs the Figma / Sketch files used to produce it). It's common for renderings to be made available online—although usually not explicitly licensed—but I more rarely see source made available.