That's really not true, there's still a lot of games out there with really solid gameplay. The last two games I bought (Halo2 and Outrun2) had fantastic gameplay, Outrun2 is probably one of the greatest arcade games of all time.
I'm not a big graphics whore, I think the most beautiful games tend to be 2D, but some games are just unplayable because of their graphics. Tried going back and playing those N64, Playstation or 3D Saturn games? It's painful going back to those games.
My bigger complaint with graphics comes from games like the GTA series, where the gameply is there but the graphics blow. If the games had been designed for the GC or XBox, they wouldn't look like the ass they look like. The same can be said for a lot of PS2 games. Does it ruin the game? No, it's just frustrating to know that it could be better.
Given that the video games industry is bigger than the movie industry and growing, that won't be happening anytime soon. The three-company setup in the industry right now almost guarantees there won't be a repeated Atari fiasco as well, if one company messes up, there's two more to take it's place...
But very little. Outrun2 yes and 2D games are the best.