Flashy graphics doth not a good game make... I've lost count of the games that are purely eye candy with sod all underneath that.
Take Elite for example, the original was wireframe with no colour, but the game itself rocked!
Also, what about Jet Set Willy, Asteroids, Chuckie Egg, and Arkanoid?
It's not nostalgia in a lot of cases, it's because they were landmark games, there's no new ground being broken these days in the games market.