It's popularity I think comes from a) it's brain dead easy to get running while also being a very usable and nice hyprland config b) it's from DHH which has cult following status

I'd argue there's a fairly big niche of people who want a tiling WM but also don't want to have to start from scratch, figure out what accompanying utilities and programs they want to satisfy things like runner/menu, status bar, etc.

Other dots aren't as opinionated, or don't come with such a detailed user guide that Omarchy does, nor a set up script.

I'd even argue that Omarchy isn't really for other Linux users looking to distro hop, but like Omakub, it's for mac users curious about Linux, wanting an equally opinionated set up.