If you're wanting something similar to SteamOS right now that has much wider hardware support for your gaming handhelds like the Lenovo Legion Go, ASUS ROG Ally, GPD, Ayaneo or even your laptop / desktop then Bazzite is likely one of the best choices.
If you’re used to Steam, gaming mode gives it a big picture mode UI, it’s the main UI for the Steam Deck. However like on the Steam Deck with SteamOS, it also has a desktop mode and Bazzite give you options for other Desktop Environments like GNOME and Budgie (which is coming soon) and also KDE Plasma which is what comes stock on the Steam Deck.
If you’re used to Steam, gaming mode gives it a big picture mode UI, it’s the main UI for the Steam Deck. However like on the Steam Deck with SteamOS, it also has a desktop mode and Bazzite give you options for other Desktop Environments like GNOME and Budgie (which is coming soon) and also KDE Plasma which is what comes stock on the Steam Deck.