Considering PS2 sold more units than the NES and SNES combined, I'd say there's two likely scenarioes:
1. A WHOLE lot of ****ing
2. A bunch of people who weren't interested in Nintendo systems bought PlayStations.
Look, I like to bash Sony as much as the next guy, but to discount what they did for the market over the last decade is folly. And to suggest that there is one magic bullet way to design games that guarantees success and total mass market domination is just as ludicrous.
This happens all the time, in every industry. Someone scores an iPod, or a Walkman, or a Google, or a DS, and then everybody trips over themselves trying to extrapolate the magic formula that made the item such a hit. They make charts, they do surveys, they reference data, and the really ambitious write books that explain how
you too can enjoy the fantastic success by just following these simple steps!
The TRUTH is that sometimes companies win, and sometimes they lose. Right now Nintendo is winning. If they keep winning Sony, MS and anyone else trying to compete in the video game market will emulate their methods in an attempt to repeat their success. That is until someone else comes along with a video game idea different than what's currently popular, and they find wild success and adulation. Then the process starts all over again.
Beware those who tell you there is any truth to business besides uncertainty. They are probably trying to sell you something.