That’s long overdue. Many removed it in favor of flatpaks. There were still some minor issues with flatpak. I guess those are resolved now

Didn’t know what uBlue was, so here: https://universal-blue.org/

"The Universal Blue project builds a diverse set of continuously delivered operating system images using bootc. That’s nerdspeak for the ultimate Linux client: the reliability of a Chromebook, but with the flexibility and power of a traditional Linux desktop.

These images represent what’s possible when a community focuses on sharing best practices via automation and collaboration. One common language between dev and ops, and it’s finally come to the desktop.

We also provide tools for users to build their own image using our templates and processes, which can be used to ship custom configurations to all of your machines, or finally make the Linux distribution you’ve long wished for, but never had the tools to create.

At long last, we’ve ascended."

Do an update, this was an error due to moving over to dnf5.

I don’t know the reasoning, but since the uBlue main image is meant to be a sort of base template (iirc), my guess is there was a decision to downstream all of those additions, to allow child distributions to improve the build process and make their own opinionated changes.

You might try asking on the uBlue discord.