i havent looked into them in a while but arent they more expensive? reducing cost is realistic if valve could pull off the same punch as a steamdeck by using similar but better powered SoCs, or be able to sell at a loss as a calculated risk to get people spending on steam. sony and microsoft do it and it works.
make it convertible as a computer, like the deck is and as upgradable as possible (at least a gpu slot pls!) and you got an easy low cost linux based introduction to the pc ecosystem. with all money going to portables i dunno if they would do it but it would change that part of the game, it would certainly make it more open.