If you're running Cosmos as a docker container instead of as the base operating system, then it just acts as a container management UI and reverse proxy. There's some other stuff built in with their Constellation VPN (similar to wireguard/tail scale) and the app store for 1-click installs. But you don't get any of the storage management tools from the OS version.
You can still manage and install docker containers like normal or with compose files and have them show up in Cosmos.
The UI regressed to Windows Aero from Vista. Took 20 years, but they made it full circle.