On paper specs isnt important for handheld... The no.1 thing is price, no.2 is battery life... If you are going to sell it for over $1000, vast maority of the pple arent interested...
The most popular handheld today is the mobile phone. Other than a few premium models, many are cheaper than usd500 and does gaming and more.
If you are talking about PC games on the go... Well, many pple could live without.. play mobile phone games when on the go and swtch to pc at home
Another would be size, perhaps even more important than battery life. If the device is too large to easily carry with you, that kind of defeats the point of making it a "portable" device. Something like a smartphone can be discretely tucked into a large pocket when not in use, whereas this device, as well as the Steam Deck, are arguably too bulky to attain mass-market appeal. Even the notably smaller Nintendo Switch is edging into the awkward-to-transport size range, but that has some unique control features, a low entry price, and high-profile exclusives to help sell it. And the Steam Deck might be similarly bulky, but at least comes in at a moderate starting price, with the backing of the most popular PC gaming platform behind it.
With this device, it seems the only thing it really has to offer over the competition is better hardware specs. But with a price likely to be higher than many budget gaming laptops, and a size that doesn't make it all that much more portable, it begs the question of why one wouldn't simply pay less for a faster laptop instead for their semi-portable gaming needs.