You can apply a glossy screen protector to the 1tb model, and you can apply a matte screen protector to the 512gb model. There’s really way too much discussion about this shit.
Imo get the 512gb, it’s cheaper. Shove in a 1tb, 2tb or more drive I the future if you need more space. I’ve got a 1tb microSD card so a 512gb does me fine for now.

This picture makes me want an old model more than any other.
Ugh. I can’t justify buying another without a big perfomance gain though.

If I were a bigger gamer (only play games occasionally now). I’d definitely get a windows handheld to compliment my steam deck to play the latest AAA DRM games.
But as I only play games infrequently, and mostly games that have been out for a bit first, just having a steak deck is enough for me.

it means these upgrades will be reflected in the Steam Deck 2 eventually.

There’s absolutely no guarantee that is the case.