Young adults read the most books, statistically. It is biggest market. They read less then previous generation used to read at their age, but they still read more then previous generation reads now.
Absolutely. When I was a kid, I'd skip tutorials, I'd skip text in RPGs. I just wanted to get to the ACTION.
As I'm older, I'm actually able to sit down and appreciate slower-form / long-form RPGs with lots of text that adds the real texture to the graphics--which only really form a symbolic / tactical representation of the world, and the flavors, the smells, all come from text. In many ways, the game mechanics of most games are all the same and the flavor is what sets them apart.
Exile 3: Ruined World for example. (And the two remakes Avernum 1 and 2 series.) Are legendary for their novel length text and story.
When I was a kid, I spent my time playing with character options, trying out new diseases (more diseases = less XP per level--neat idea) and skipping texts to explore. But then I'd always get stuck at some point because I missed a key piece of text when I skimmed
(That's actually one "game sin" I hate in many games. If you're going to have important text buried in tons of flavor text, COLOR or EMPHASISE IT. The last thing you want is a player who gets tired one night, skips ONE line that was important, and then hates your game because they're frustrated without information they should have had.)