TL;DR: Antec is going to be selling a Steam Deck competitive device, based on the Ayaneo Slide. The device has a slide up screen that reveals a keyboard, which is good because using desktop windows is much easier with a keyboard. However the device’s lowest estimated power draw at low/no load is 15w, meaning it will use comparable power to the deck running at max power. This means the battery life will probably be pretty rough when compared to the Deck. It will also likely have a much higher price point.
I’ve never had resolution complaints on my handheld screen. There’s been scaling troubles and other graphics shortcomings, but resolution has never been a problem, how close are you holding the deck to your face?
Its about the same difference, but you can definitely tell the difference between 1600p and 720p.
Where are you getting 1600p screens that are 9 inches diagonal?
And what hardware are you using that puts 1600p into a 9 inch screen? Sounds a lot like overkill, or bigger numbers for the sake of having bigger numbers.