I ordered one because I'd like to build a simple game for it, my dev career started in z80 assembly building monochrome games for the TI-83+, so 100% nostalgia for me.
Even at the time, the screen on the GameBoy was such garbage. The lack of a light didn't help either. But even with a backlight, all LCD screens were bad. I remember how washed out the Lynx and GameGear screens were.
The replacement screens you can get for them now are amazing.
I grew up mostly on the NES and earlier systems, and IMO from approximately the Super Nintendo on, game system generations have all delivered about the same amount of happiness (though some individual systems were major duds, of course). It's just a matter of what you're used to. Admittedly, the frustration level of average games on the NES and other earlier systems kept them from being quite the joy-generating devices that later ones would be.