I know early adopters / enthusiasts and those with thick wallets really want new tech on a swift, regular, cycle, but honestly, these people are a small minority. The majority don't even buy into a console cycle till years 3-5 (usually after a revision and a significant price drop), and those people still want to have their 'new' console be 'new/relevant' for several years.
Appeasing the early adopters has some merit, but at the high risk of burning out the loyal base. $400-$500 is a huge purchase for many families, and given it's a gaming system, it's a pure luxury item. A gen of about 8 years ($50 a year for hardware, at $400) is about the right price point. Someone buying in late at $300 still is getting around $50 a year.
While other markets support many iterations, the console market is historically different. Many console owners like to have the 'top of the line' machine, even if it's years old and no longer 'cutting edge' compared to PCs. That's not the draw - the draw is being able to pick the newest game off the shelf at the store and knowing it'll play and be 'just as good' as the guy down the street playing the same game, with no hassle.