I'm sorry but this does not resemble a 'Steam Deck' at all.
It is just another horizontal 'retro rig' making use of the RK3326 (in which there are nearly COUNTLESS examples/variations).
Sadly lacking the CPU/GPU power or even Wifi to be a viable Streaming client, personally IDK why the endless stream of these devices are making their way to market.
The E6 is a relatively new retro gaming handheld built with the task of emulating up to Sony PlayStation Portable games. Available for under $50, the E6 gaming handheld resembles the Valve Steam Deck, albeit on a much smaller scale.