Omarchy may have started out as dotfiles and scripts, but now it's a formal collection of Arch packages. I'm not sure if all their packages have been upstreamed to Arch, but I expect not:

https://github.com/omacom/omarchy-pkgs/tree/master/pkgbuilds

Regolith may also seem like it would also be a "collection of dotfiles" to customize Sway and other things, but it also has a number of packages that they've developed or patched as well.

For example, I think both Omarchy and Regolith developed their own launchers. Regolith created Ilia, and I think Omarchy created something to replace Walker.

One thing both projects have been in common is they prioritized consistent theming across a range of applications. In both cases, it required some customizations to various projects to get them to read centralized theme settings or otherwise respond to theming changes.