Endless OS 6 is available now as a free upgrade for existing users and a free download for new installations! Let’s take a look at what’s new and improved in the latest release of our completely free, user-friendly operating system packed with educational tools, games, and more.
Torvalds only worked on the kernel, not a whole OS. Also, it isn't true that he was alone in the first couple of years. He had commits by others almost immediately after release.
Well like any distro it's not just the desktop environment (Gnome) but follows an opinionated setup and design. There's bundled packages, design tweaks to the DE, config changes to packaged software, different default apps and repos for the base OS (Debian in this case) and other tweaks. Link below should explain this all in more depth.