For what it's worth.. it's based on Ubuntu 24.04, which is where their version starts... they're much more up to date on the kernel, a lot of the packages are newer than upstream as well. It's a more current LTS than what Ubuntu offers, but they keep the version number.

Also, they didn't do a release while COSMIC desktop was under development, and the release cycle was alpha/beta on a full baseline to match the COSMIC development... unless you think you can develop a full DE in Rust faster than that.